0000929008-26-000014 | 10-Q | XBRL Viewer

Equity (Details) - USD ($) $ in Millions	3 Months Ended
Equity (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Equity [Abstract]
Treasury Stock, Value, Acquired, Cost Method	$ 25.3	$ 25.3

- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References + Details

GOODWILL (Notes)

3 Months Ended

Mar. 31, 2026

Intangible Asset, Goodwill and Other [Abstract]

Intangible Asset and Goodwill

The following table sets forth the changes in the carrying value of goodwill by reportable segment, which correspond to our reporting units, for the period presented:


	EES		CSS		UBS		Total
	(In millions)
Beginning balance, January 1, 2026	$	843.8	$	1,354.1	$	1,145.5	$	3,343.4


Foreign currency exchange rate changes	(7.5)		(0.7)		(3.6)		(11.8)
Ending balance, March 31, 2026	$	836.3	$	1,353.4	$	1,141.9	$	3,331.6

The components of intangible assets are as follows:


		As of
		March 31, 2026						December 31, 2025
	Life (in years)	Gross Carrying Amount(1)		Accumulated Amortization(1)		Net Carrying Amount		Gross Carrying Amount(1)		Accumulated Amortization(1)		Net Carrying Amount
Intangible assets:		(In millions)
Trademarks	Indefinite	$	791.0	$	—	$	791.0	$	791.6	$	—	$	791.6
Customer relationships	9 - 20	1,504.9		(572.7)		932.2		1,523.6		(570.2)		953.4
Distribution agreements	8	10.7		(1.6)		9.1		10.7		(1.3)		9.4
Trademarks	5 and 12	15.5		(14.6)		0.9		15.5		(14.0)		1.5
Software	7	16.0		(4.0)		12.0		16.0		(3.4)		12.6
Technology know-how	5	0.9		(0.2)		0.7		0.9		(0.2)		0.7
		$	2,339.0	$	(593.1)	$	1,745.9	$	2,358.3	$	(589.1)	$	1,769.2

(1) Excludes the original cost and related accumulated amortization of fully-amortized intangible assets.

Amortization expense related to intangible assets totaled $21.8 million and $22.2 million for the three months ended March 31, 2026 and 2025, respectively.

The following table sets forth the remaining estimated amortization expense for intangible assets for the next five years and thereafter:


For the year ending December 31,	(In millions)
Remaining 2026	$	63.8
2027	83.2
2028	81.6
2029	80.5
2030	74.3
Thereafter	571.5
Total	$	954.9

SCHEDULE OF SHARE-BASED COMPENSATION, STOCK OPTIONS AND STOCK APPRECIATION RIGHTS AWARD ACTIVITY (Details) - Stock Appreciation Rights (SARs) [Member] - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	346,866	411,759
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 58.68	$ 59.12
Granted (in shares)	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	(64,504)
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	$ 61.57
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	(389)
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	$ 42.44
Weighted Average Remaining Contractual Term, Outstanding (in years)	3 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 74.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	346,866
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 58.68
Weighted Average Remaining Contractual Term, Exercisable (in years)	3 years 4 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 74.6
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 14.7

DEBT (Tables)

3 Months Ended

Mar. 31, 2026

Debt Disclosure [Abstract]

Schedule of Debt

The following table sets forth Wesco's outstanding indebtedness:


	As of
	March 31, 2026		December 31, 2025
	(In millions)
International lines of credit	$	1.2	$	5.6
Accounts Receivable Securitization Facility	120.0		1,300.0
Revolving Credit Facility	251.5		581.5
7.250% Senior Notes due 2028, less debt discount of $2.8 and $3.1 in 2026 and 2025, respectively	1,322.2		1,321.9
6.375% Senior Notes due 2029	900.0		900.0
5.250% Senior Notes due 2031	650.0		—
6.625% Senior Notes due 2032	850.0		850.0
6.375% Senior Notes due 2033	800.0		800.0
5.500% Senior Notes due 2034	850.0		—
Finance lease obligations	76.8		67.3
Total debt	5,821.7		5,826.3
Less: Unamortized debt issuance costs	(60.8)		(44.9)
Less: Short-term debt and current portion of long-term debt	(22.8)		(25.0)
Total long-term debt	$	5,738.1	$	5,756.4

STOCK-BASED COMPENSATION AWARDS (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 14.7
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	139,312	215,603
Granted, Weighted Average Fair Value (in dollars per share)	$ 296.15	$ 179.83
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	48,440	72,302
Granted, Weighted Average Fair Value (in dollars per share)	$ 321.94	$ 191.72
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross	58,729	84,476
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 124.11	$ 76.59
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 0.7

FAIR VALUE (Notes)	3 Months Ended
FAIR VALUE (Notes)	Mar. 31, 2026
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	10. FAIR VALUE OF FINANCIAL INSTRUMENTS The Company’s financial instruments primarily consist of cash and cash equivalents, accounts receivable, accounts payable, bank overdrafts, outstanding indebtedness, foreign currency forward contracts, and benefit plan assets. Except for benefit plan assets, outstanding indebtedness and foreign currency forward contracts, the carrying value of the Company’s other financial instruments approximates fair value. The assets of the Company’s various defined benefit plans primarily comprise common/collective/pool funds (i.e., mutual funds). These funds are valued at the net asset value (“NAV”) of shares held in the underlying funds. Investments for which fair value is measured using the NAV per share practical expedient are not classified in the fair value hierarchy. The Company uses a market approach to determine the fair value of its debt instruments, utilizing quoted prices in active markets, interest rates and other relevant information generated by market transactions involving similar instruments. Therefore, the inputs used to measure the fair value of the Company’s debt instruments are classified as Level 2 within the fair value hierarchy. The carrying value of Wesco’s debt instruments with fixed interest rates was $5,372.2 million and $3,871.9 million as of March 31, 2026 and December 31, 2025, respectively. The estimated fair value of this debt was $5,424.4 million and $4,004.2 million as of March 31, 2026 and December 31, 2025, respectively. The reported carrying values of Wesco’s other debt instruments, including those with variable interest rates, approximated their fair values as of March 31, 2026 and December 31, 2025. The Company purchases foreign currency forward contracts to reduce the effect of fluctuations in foreign currency-denominated accounts on its earnings. The foreign currency forward contracts are not designated as hedges for accounting purposes. The Company’s strategy is to negotiate terms for its derivatives and other financial instruments to be highly effective, such that the change in the value of the derivative offsets the impact of the underlying hedge. Its counterparties to foreign currency forward contracts have investment-grade credit ratings. The Company regularly monitors the creditworthiness of its counterparties as a risk mitigation effort to protect the value of its derivatives. The Company does not hedge 100% of its foreign currency-denominated accounts. In addition, the results of hedging can vary significantly based on various factors, such as the timing of executing foreign currency forward contracts versus the movement of currencies, as well as fluctuations in the account balances throughout each reporting period. The fair value of foreign currency forward contracts is based on the difference between the contract rate and the current price of a forward contract with an equivalent remaining term. The fair value of foreign currency forward contracts is measured using observable market information. These inputs are considered Level 2 in the fair value hierarchy. At March 31, 2026 and December 31, 2025, foreign currency forward contracts were revalued at then-current foreign exchange rates with the changes in valuation reflected directly in Other non-operating (income) expense in the Condensed Consolidated Statements of Income and Comprehensive Income offsetting the transaction gain (loss) recorded on foreign currency-denominated accounts. The gross and net notional amounts of foreign currency forward contracts outstanding were approximately $322.5 million and $286.3 million, at March 31, 2026 and December 31, 2025, respectively. While all of the Company’s foreign currency forward contracts are subject to master netting arrangements with its counterparties, assets and liabilities related to these contracts are presented on a gross basis within the Condensed Consolidated Balance Sheets. The gross fair value of assets and liabilities related to foreign currency forward contracts were immaterial.
Derivatives and Fair Value	The Company purchases foreign currency forward contracts to reduce the effect of fluctuations in foreign currency-denominated accounts on its earnings. The foreign currency forward contracts are not designated as hedges for accounting purposes. The Company’s strategy is to negotiate terms for its derivatives and other financial instruments to be highly effective, such that the change in the value of the derivative offsets the impact of the underlying hedge. Its counterparties to foreign currency forward contracts have investment-grade credit ratings. The Company regularly monitors the creditworthiness of its counterparties as a risk mitigation effort to protect the value of its derivatives. The Company does not hedge 100% of its foreign currency-denominated accounts. In addition, the results of hedging can vary significantly based on various factors, such as the timing of executing foreign currency forward contracts versus the movement of currencies, as well as fluctuations in the account balances throughout each reporting period. The fair value of foreign currency forward contracts is based on the difference between the contract rate and the current price of a forward contract with an equivalent remaining term. The fair value of foreign currency forward contracts is measured using observable market information. These inputs are considered Level 2 in the fair value hierarchy. At March 31, 2026 and December 31, 2025, foreign currency forward contracts were revalued at then-current foreign exchange rates with the changes in valuation reflected directly in Other non-operating (income) expense in the Condensed Consolidated Statements of Income and Comprehensive Income offsetting the transaction gain (loss) recorded on foreign currency-denominated accounts. The gross and net notional amounts of foreign currency forward contracts outstanding were approximately $322.5 million and $286.3 million, at March 31, 2026 and December 31, 2025, respectively. While all of the Company’s foreign currency forward contracts are subject to master netting arrangements with its counterparties, assets and liabilities related to these contracts are presented on a gross basis within the Condensed Consolidated Balance Sheets. The gross fair value of assets and liabilities related to foreign currency forward contracts were immaterial.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

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+ Details

REVENUE (Tables)

3 Months Ended

Mar. 31, 2026

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue [Table Text Block]

The following table disaggregates Wesco’s Net sales by geography for the periods presented:


	Three Months Ended
	March 31
(In millions)	2026		2025
United States	$	4,504.6	$	3,974.6
Canada	827.1		712.8
Other International(1)	748.4		656.3
Total by geography(2)	$	6,080.1	$	5,343.7

INCOME TAXES	3 Months Ended
INCOME TAXES	Mar. 31, 2026
Income Tax Disclosure [Abstract]
INCOME TAXES	The effective tax rate for the three months ended March 31, 2026 and 2025 was 21.8% and 23.4%, respectively. The decrease in the effective tax rate is largely driven by higher discrete income tax benefits relating to the exercise and vesting of stock-based awards. For the three months ended March 31, 2026 and 2025, the effective tax rate reflects discrete income tax benefits of $7.7 million and $4.7 million, respectively, from the exercise and vesting of stock-based awards. These discrete income tax benefits reduced the effective tax rate in such periods by approximately 3.9 and 3.0 percentage points, respectively. During the three months ended March 31, 2026 and 2025, the Company purchased $1.0 million and $53.3 million, respectively, of transferable clean energy tax credits to reduce its U.S. federal income tax liability. The Company has taken appropriate measures to mitigate the transferee liability associated with these tax credits, including but not limited to conducting due diligence to confirm the eligibility of the underlying projects or production, as applicable, for the tax credits and the eligibility of the tax credits for transfer, obtaining appropriate contractual protections from the sellers, and obtaining tax credit insurance and/or seller guarantees. The effective tax rate, excluding discrete income tax benefits, differs from the federal statutory income tax rate due primarily to state income taxes, nondeductible expenses, and the tax impact of international operations. There have been no material adjustments to the Company's assessment of uncertain tax positions since December 31, 2025. In October 2021, one of the Company’s Mexican affiliates received a tax assessment from the Mexican tax authorities related to its 2012 income tax return which was approximately $33.4 million as of December 31, 2025. The Company believed the assessment was without merit and the Company's Mexican affiliate filed an annulment lawsuit in the Mexican Federal Court of Administrative Justice (the “Court”). The Company expected to prevail in this litigation and, accordingly, did not recognize a liability for this assessment in its Consolidated Financial Statements. On April 23, 2026, the Company received the written decision of the Court. The Company is still evaluating the Court's decision. To the extent that the decision is unfavorable to the Company's Mexican affiliate, it will file an appeal for constitutional review of the lower court decision with the Mexican Federal Collegiate Circuit Court. The Company maintains that it ultimately expects to prevail upon final resolution of the matter.

- Definition

The entire disclosure for income tax.

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+ Details

DEBT - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended			26 Months Ended	36 Months Ended	38 Months Ended
DEBT - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2026	Mar. 31, 2026	Apr. 14, 2031	Apr. 14, 2030	Apr. 14, 2029	Apr. 14, 2028	Apr. 14, 2034	Apr. 14, 2029
Debt Instrument [Line Items]
Percentage of principal amount of Senior Notes accelerated under default		25.00%
5.250% Senior Notes due 2031
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Apr. 15, 2031
Debt Instrument, Interest Rate, Stated Percentage		5.25%
Discount percentage of par value		100.00%
Debt Issuance Costs, Gross		$ 8.3
5.250% Senior Notes due 2031 \| Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed			100.00%	101.3125%	102.625%	35.00%
5.500% Senior Notes due 2034
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Apr. 15, 2034
Debt Instrument, Interest Rate, Stated Percentage		5.50%
Debt Issuance Costs, Gross		$ 10.8
5.500% Senior Notes due 2034 \| Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed			101.375%	102.75%			100.00%	35.00%
7.250% Senior Notes due 2028
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 1,325.0
Debt Instrument, Interest Rate, Stated Percentage		7.25%
7.250% Senior Notes due 2028 \| Forecast [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed	100.00%

Segment Reporting (Details) $ in Millions	3 Months Ended
Segment Reporting (Details) $ in Millions	Mar. 31, 2026 USD ($) distribution_centers	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($)
Segment Reporting [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 6,080.1	$ 5,343.7
Other Nonoperating Income (Expense)	(0.4)	0.2
Assets	16,964.7		$ 16,494.9
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	4,788.3	4,218.1
Selling, general, and administrative payroll expenses	468.3	428.8
Segment Reporting, Other Segment Item, Amount	284.6	257.4
Depreciation and amortization	50.7	48.4
Stock-based compensation expense	16.1	10.2
Selling, general and administrative expense	947.6	836.3
Interest Income (Expense), Nonoperating, Net	(96.7)	(86.3)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ 197.2	$ 154.4
Segment Reporting, Other Segment Item, Composition, Description	(2) Other segment items primarily include allocated expenses (which includes employee-related allocations), transportation costs, facility costs (including rent and utilities), employee expenses (including travel and entertainment), credit losses, real estate and personal property taxes, supplies, professional and consulting fees, and sales promotion expenses.	(2) Other segment items primarily include allocated expenses (which includes employee-related allocations), transportation costs, facility costs (including rent and utilities), employee expenses (including travel and entertainment), credit losses, professional and consulting fees, supplies, real estate and personal property taxes, sales promotion expenses, and gains (losses) on the sale, disposal, or abandonment of property and equipment.
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	Chief Executive Officer [Member]
Number of Reportable Segments \| distribution_centers	3
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description	The CODM evaluates the performance of the Company’s reportable segments based on Adjusted earnings before interest, taxes, depreciation and amortization (“Adjusted EBITDA”), which is the Company’s measure of segment profit or loss.
Operating Segments
Segment Reporting [Line Items]
Adjusted EBITDA	$ 538.9	$ 439.4
Other Nonoperating Income (Expense)	19.5	15.1
Assets	15,853.8		15,486.4
Depreciation and amortization	41.5	39.0
Stock-based compensation expense	3.3	2.7
EES
Segment Reporting [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,244.2	2,065.3
Adjusted EBITDA	185.0	142.6
Other Nonoperating Income (Expense)	6.8	4.4
Assets	4,992.5		4,860.8
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	1,711.0	1,594.1
Selling, general, and administrative payroll expenses	228.4	212.1
Segment Reporting, Other Segment Item, Amount	$ 119.8	$ 116.5
Adjusted EBITDA Margin Percentage	8.20%	6.90%
Depreciation and amortization	$ 13.2	$ 12.2
CSS
Segment Reporting [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,478.9	2,000.3
Adjusted EBITDA	223.2	158.5
Other Nonoperating Income (Expense)	13.1	10.9
Assets	7,018.2		6,827.0
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	1,960.7	1,580.8
Selling, general, and administrative payroll expenses	178.3	160.5
Segment Reporting, Other Segment Item, Amount	$ 116.7	$ 100.5
Adjusted EBITDA Margin Percentage	9.00%	7.90%
Depreciation and amortization	$ 19.8	$ 19.0
UBS
Segment Reporting [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,357.0	1,278.1
Adjusted EBITDA	130.7	138.3
Other Nonoperating Income (Expense)	(0.4)	(0.2)
Assets	3,843.1		3,798.6
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	1,116.6	1,043.2
Selling, general, and administrative payroll expenses	61.6	56.2
Segment Reporting, Other Segment Item, Amount	$ 48.1	$ 40.4
Adjusted EBITDA Margin Percentage	9.60%	10.80%
Depreciation and amortization	$ 8.5	$ 7.8
Corporate Segment
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	(19.9)	(14.9)
Assets	1,110.9		$ 1,008.5
Depreciation and amortization	9.2	9.4
Selling, general and administrative expense	191.4	147.4
Interest Income (Expense), Nonoperating, Net	$ 96.7	$ 86.3

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	3 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Gross Profit [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 6,080.1	$ 5,343.7
Cost of goods sold	4,788.3	4,218.1
Operating Expenses [Abstract]
Selling, general and administrative expense	947.6	836.3
Depreciation and amortization	50.7	48.4
Income from operations	293.5	240.9
Interest Income (Expense), Nonoperating, Net	96.7	86.3
Other Nonoperating Income (Expense)	(0.4)	0.2
Income before income taxes	197.2	154.4
Provision for income taxes	43.1	36.1
Net income	154.1	118.3
Net (loss) income attributable to noncontrolling interest	0.3	(0.1)
Net income attributable to WESCO International, Inc.	153.8	118.4
Preferred Stock Dividends, Income Statement Impact	0.0	14.4
Net Income (Loss) Available to Common Stockholders, Basic	$ 153.8	$ 104.0
Basic (in dollars per share)	$ 3.16	$ 2.13
Diluted (in dollars per share)	$ 3.11	$ 2.10
Comprehensive Income:
Foreign currency translation adjustment	$ (26.4)	$ 16.1
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(0.5)	(0.3)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(26.9)	15.8
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	127.2	134.1
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	0.3	(0.1)
Comprehensive income attributable to WESCO International, Inc.	126.9	119.8
Revenue from Contract with Customer, Excluding Assessed Tax	$ 6,080.1	$ 5,343.7

DEBT (Notes)

3 Months Ended

Mar. 31, 2026

Debt Instrument [Line Items]

Debt Disclosure [Text Block]

9. DEBT

The following table sets forth Wesco's outstanding indebtedness:


	As of
	March 31, 2026		December 31, 2025
	(In millions)
International lines of credit	$	1.2	$	5.6
Accounts Receivable Securitization Facility	120.0		1,300.0
Revolving Credit Facility	251.5		581.5
7.250% Senior Notes due 2028, less debt discount of $2.8 and $3.1 in 2026 and 2025, respectively	1,322.2		1,321.9
6.375% Senior Notes due 2029	900.0		900.0
5.250% Senior Notes due 2031	650.0		—
6.625% Senior Notes due 2032	850.0		850.0
6.375% Senior Notes due 2033	800.0		800.0
5.500% Senior Notes due 2034	850.0		—
Finance lease obligations	76.8		67.3
Total debt	5,821.7		5,826.3
Less: Unamortized debt issuance costs	(60.8)		(44.9)
Less: Short-term debt and current portion of long-term debt	(22.8)		(25.0)
Total long-term debt	$	5,738.1	$	5,756.4

5.250% Senior Notes due 2031

5.500% Senior Notes due 2034

On February 27, 2026, Wesco Distribution, Inc. (“Wesco Distribution”) issued $650 million aggregate principal amount of 5.250% Senior Notes due 2031 (the “2031 Notes”) and $850 million aggregate principal amount of 5.500% Senior Notes due 2034 (the “2034 Notes” and, together with the 2031 Notes, the “2031 and 2034 Notes”). The 2031 and 2034 Notes were issued at prices of 100% of the aggregate principal amounts thereof. Wesco incurred costs related to the issuance of the 2031 and 2034 Notes totaling $8.3 million and $10.8 million, respectively, which were recorded as a reduction to the carrying value of the debt and are being amortized over the respective terms of the notes.

The 2031 and 2034 Notes were issued pursuant to, and are governed by, an indenture (the “2031 and 2034 Notes Indenture”), dated as of February 27, 2026, among Wesco Distribution, the Company, Anixter Inc., and U.S. Bank Trust Company, National Association, as trustee (the “Trustee”). The 2031 and 2034 Notes and related guarantees were issued in a private transaction exempt from the Securities Act of 1933, as amended (the “Securities Act”), and have not been, and will not be, registered under the Securities Act and may not be offered or sold in the United States absent registration or an applicable exemption from, or in a transaction not subject to, the registration requirements of the Securities Act and other applicable securities laws.

The Company intends to use the net proceeds from the issuance of the 2031 and 2034 Notes to redeem all of its outstanding 7.250% senior notes due 2028 (the “2028 Notes”) on June 15, 2026, the date at which Wesco Distribution may redeem the 2028 Notes at a redemption price equal to 100% of the principal amount, and repay a portion of the amounts outstanding under its revolving credit facility (the “Revolving Credit Facility”). Prior to redeeming the 2028 Notes, the Company used the net proceeds to temporarily repay a portion of the outstanding borrowings under its accounts receivable securitization facility (the “Receivables Facility”) and Revolving Credit Facility. The Company intends to subsequently redraw under the Receivables Facility and the Revolving Credit Facility in an aggregate amount sufficient to redeem the 2028 Notes.

On April 29, 2026, Wesco Distribution exercised its right to redeem the entire outstanding $1,325 million aggregate principal amount of the 2028 Notes, and U.S. Bank Trust Company, National Association, as successor to U.S. Bank National Association, as trustee under the 2028 Notes Indenture, issued a notice of redemption to registered holders of the 2028 Notes.

The 2031 and 2034 Notes are unsecured and unsubordinated obligations of Wesco Distribution and are guaranteed on an unsecured, unsubordinated basis by the Company and Anixter Inc. The 2031 Notes accrue interest at a rate of 5.250% per annum, payable semi-annually in arrears on April 15 and October 15 of each year. The 2031 Notes will mature on April 15, 2031. The 2034 Notes accrue interest at a rate of 5.500% per annum, payable semi-annually in arrears on April 15 and October 15 of each year. The 2034 Notes will mature on April 15, 2034.

Wesco Distribution may redeem all or a part of the 2031 Notes at any time prior to April 15, 2028 by paying a “make-whole” premium plus accrued and unpaid interest, if any, to but excluding the redemption date. In addition, any time prior to April 15, 2028, Wesco Distribution may redeem up to 35% of the original aggregate principal amount of the 2031 Notes with the net cash proceeds from certain equity offerings. At any time between April 15, 2028 and April 14, 2029, Wesco Distribution may redeem all or a part of the 2031 Notes at a redemption price equal to 102.625% of the principal amount. Between April 15, 2029 and April 14, 2030, Wesco Distribution may redeem all or a part of the 2031 Notes at a redemption price equal to 101.3125% of the principal amount. On and after April 15, 2030, Wesco Distribution may redeem all or a part of the 2031 Notes at a redemption price equal to 100% of the principal amount.

Wesco Distribution may redeem all or a part of the 2034 Notes at any time prior to April 15, 2029 by paying a “make-whole” premium plus accrued and unpaid interest, if any, to but excluding the redemption date. In addition, any time prior to April 15, 2029, Wesco Distribution may redeem up to 35% of the original aggregate principal amount of the 2034 Notes with the net cash proceeds from certain equity offerings. At any time between April 15, 2029 and April 14, 2030, Wesco Distribution may redeem all or a part of the 2034 Notes at a redemption price equal to 102.750% of the principal amount. Between April 15, 2030 and April 14, 2031, Wesco Distribution may redeem all or a part of the 2034 Notes at a redemption price equal to 101.375% of the principal amount. On and after April 15, 2031, Wesco Distribution may redeem all or a part of the 2034 Notes at a redemption price equal to 100% of the principal amount.

The 2031 and 2034 Notes Indenture contains certain covenants that, among other things, limit the Company’s and its restricted subsidiaries’ ability to incur liens on assets, make certain restricted payments, engage in certain sale and leaseback transactions or sell certain assets or merge or consolidate with or into other companies, subject to certain qualifications and exceptions, including the termination of certain of these covenants upon the 2031 and 2034 Notes receiving investment grade credit ratings.

The 2031 and 2034 Notes Indenture contains certain events of default, including, among other things, failure to make required payments, failure to comply with certain agreements or covenants, failure to pay or acceleration of certain other indebtedness, certain events of bankruptcy and insolvency, and failure to pay certain judgments. An event of default under the 2031 and 2034 Notes Indenture will allow either the Trustee or the holders of at least 25% in aggregate principal amount of the applicable series of the then-outstanding Notes to accelerate or, in certain cases, will automatically cause the acceleration of the amounts due under the applicable series of Notes.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Segment Reporting - ADJ EBITDA Reconciliations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Interest Income (Expense), Nonoperating, Net	$ (96.7)	$ (86.3)
Depreciation and amortization	50.7	48.4
Other Nonoperating Income (Expense)	0.4	(0.2)
Stock-based compensation expense	16.1	10.2
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	197.2	154.4
Operating Segments
Adjusted EBITDA	538.9	439.4
Depreciation and amortization	41.5	39.0
Other Nonoperating Income (Expense)	(19.5)	(15.1)
Stock-based compensation expense	3.3	2.7
EES
Adjusted EBITDA	185.0	142.6
Depreciation and amortization	13.2	12.2
Other Nonoperating Income (Expense)	(6.8)	(4.4)
CSS
Adjusted EBITDA	223.2	158.5
Depreciation and amortization	19.8	19.0
Other Nonoperating Income (Expense)	(13.1)	(10.9)
UBS
Adjusted EBITDA	130.7	138.3
Depreciation and amortization	8.5	7.8
Other Nonoperating Income (Expense)	$ 0.4	$ 0.2

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Operating Activities:
Net income	$ 154.1	$ 118.3
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	50.7	48.4
Stock-based compensation expense	16.1	10.2
Hosting Arrangement, Service Contract, Implementation Cost, Capitalized, Amortization Expense	11.0	3.9
Amortization of Debt Issuance Costs and Discounts	3.5	3.3
Other operating activities, net	(0.8)	(0.2)
Changes in assets and liabilities
Increase (Decrease) in Accounts Receivable	216.1	188.7
Increase (Decrease) in Accounts and Other Receivables	66.4	65.1
Inventories, net	(215.2)	(227.4)
Increase (Decrease) in Other Operating Assets	(48.4)	(35.6)
Accounts payable	449.5	343.8
Accrued payroll and benefit costs	(80.5)	(77.1)
Other current and noncurrent liabilities	3.6	(36.9)
Net cash provided by operating activities	221.4	28.0
Investing Activities:
Capital expenditures	(23.4)	(20.4)
Cash paid for acquisition	0.0	(35.2)
Other investing activities	3.5	1.2
Net cash used in investing activities	(19.9)	(54.4)
Financing Activities:
Proceeds from issuance of long-term debt	2,366.5	1,829.0
Repayments of Other Long-term Debt	2,373.1	1,729.3
Payments of Debt Issuance Costs	(19.1)	(14.0)
Payments for Repurchase of Common Stock	(22.0)	(18.0)
Payments for Repurchase of Common Stock	(25.0)	(25.0)
Payments of Ordinary Dividends, Common Stock	(24.4)	(22.1)
Payments of Ordinary Dividends, Preferred Stock and Preference Stock	0.0	14.4
Other financing activities, net	(6.7)	(3.9)
Net cash used in financing activities	(108.2)	2.3
Proceeds from (Repayments of) Short-term Debt	(4.4)	0.0
Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation	(1.5)	3.1
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	91.8	(21.0)
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation	696.6	681.6
Supplemental Cash Flow Information [Abstract]
Interest Paid, Excluding Capitalized Interest, Operating Activity	111.3	90.5
Income Tax Paid, before Refund Received	27.5	78.6
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	60.9	93.3
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	16.1	8.2
Deferred Income Tax Expense (Benefit)	$ 27.5	$ 0.9

REVENUE Deferred Revenue (Details) - USD ($) $ in Millions	3 Months Ended
REVENUE Deferred Revenue (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Revenue from Contract with Customer [Abstract]
Deferred Revenue	$ 167.0		$ 151.4	$ 141.8
Deferred Revenue, Revenue Recognized	51.2	$ 57.4
Contract with Customer, Refund Liability	$ 37.4		$ 33.7

ORGANIZATION	3 Months Ended
ORGANIZATION	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
ORGANIZATION	WESCO International, Inc. (“Wesco International”) and its subsidiaries (collectively, “Wesco” or the “Company”), headquartered in Pittsburgh, Pennsylvania, is a leading provider of business-to-business distribution, logistics services and supply chain solutions. The Company has operating segments comprising three strategic business units consisting of Electrical & Electronic Solutions (“EES”), Communications & Security Solutions (“CSS”) and Utility & Broadband Solutions (“UBS”).

EARNINGS PER SHARE (Details) - USD ($) $ in Millions	3 Months Ended
EARNINGS PER SHARE (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	100,000	500,000
Treasury Stock, Value, Acquired, Cost Method	$ 25.3	$ 25.3
Treasury Stock, Common [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Treasury Stock, Shares, Acquired	92,657	153,228
Treasury Stock, Shares, Acquired	92,657	153,228
Treasury Stock, Value, Acquired, Cost Method	$ 25.3	$ 25.3

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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+ Details

- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References + Details

Equity

3 Months Ended

Mar. 31, 2026

Equity [Abstract]

Stockholders' Equity Note Disclosure

Share Repurchases

On May 31, 2022, the Company’s Board of Directors adopted a resolution authorizing the repurchase of up to $1 billion of the Company’s common stock and 10.625% Series A Fixed-Rate Reset Cumulative Perpetual Preferred Stock (the “Series A Preferred Stock”). The share repurchase authorization has no expiration date and may be modified, suspended, or terminated at any time without prior notice.

During the three months ended March 31, 2026 and 2025, the Company entered into spot repurchase transactions through a broker to purchase 92,657 and 153,228 shares of its common stock, respectively, in the open market for cash totaling $25.3 million, including excise taxes, in each period. Wesco funded the repurchases with available cash and borrowings under its accounts receivable securitization and revolving credit facilities.

Dividends

The Company’s dividends on common stock are declared at the discretion of the Board of Directors. The following table is a summary of cash dividends declared and paid on the Company’s common stock for the three months ended March 31, 2026:

Date Declared

Record Date

Payment Date

Amount Per Share

Dividend Payment (in millions)

February 26, 2026

March 13, 2026

March 31, 2026

0.500

24.4

The following table is a summary of cash dividends declared and paid on the Company’s common stock for the three months ended March 31, 2025:

Date Declared

Record Date

Payment Date

Amount Per Share

Dividend Payment (in millions)

February 27, 2025

March 14, 2025

March 31, 2025

0.454

22.1

No quarterly cash dividends were paid on the Company’s Series A Preferred Stock during the three months ended March 31, 2026, as the Series A Preferred Stock was redeemed in June 2025. During the three months ended March 31, 2025, the Company's Board of Directors declared and the Company paid quarterly cash dividends of $0.664 per depositary share relating to its Series A Preferred Stock totaling $14.4 million.

- Definition

The entire disclosure for equity.

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+ Details

SCHEDULE OF EARNINGS PER SHARE, BASIC AND DILUTED (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Earnings Per Share [Abstract]
Net income (loss) attributable to WESCO International, Inc.	$ 153.8	$ 118.4
Weighted average common shares outstanding used in computing basic earnings per share (in shares)	48.7	48.8
Common shares issuable upon exercise of dilutive stock options (in shares)	0.8	0.8
Weighted average common shares outstanding and common share equivalents used in computing diluted earnings per share (in shares)	49.5	49.6
Diluted (in dollars per share)	$ 3.11	$ 2.10
Basic (in dollars per share)	$ 3.16	$ 2.13
Net Income (Loss) Available to Common Stockholders, Basic	$ 153.8	$ 104.0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.1	0.5
Preferred Stock Dividends, Income Statement Impact	$ 0.0	$ 14.4

STOCK-BASED COMPENSATION (Notes)

3 Months Ended

Mar. 31, 2026

Share-Based Payment Arrangement [Abstract]

STOCK-BASED COMPENSATION

Wesco’s stock-based compensation awards consist of stock options, stock-settled stock appreciation rights, restricted stock units and performance-based awards. Compensation cost for all stock-based awards is measured at fair value on the date of grant and compensation cost is recognized, net of estimated forfeitures, over the service period for awards expected to vest. The fair value of stock options and stock-settled stock appreciation rights is determined using the Black-Scholes model. The fair value of restricted stock units is determined by the grant-date closing price of Wesco’s common stock. The fair value of performance-based awards with performance conditions is determined by a Monte Carlo simulation as well as the grant-date closing price of Wesco’s common stock. The forfeiture assumption is based on Wesco’s historical participant behavior that is reviewed on at least an annual basis. For stock options and stock-settled stock appreciation rights that are exercised, and for restricted stock units and performance-based awards that vest, shares are issued out of Wesco's outstanding common stock.

Stock options and stock-settled stock appreciation rights vest ratably over a three-year period and terminate on the tenth anniversary of the grant date unless terminated sooner under certain conditions. Restricted stock units awarded under the WESCO International, Inc. 2021 Omnibus Incentive Plan, which was adopted on May 27, 2021, typically vest ratably over a three-year period on each of the first, second and third anniversaries of the grant date. Vesting of performance-based awards is based on a three-year performance period, and the number of shares earned, if any, depends on the attainment of certain performance levels, as described below. Outstanding awards would vest upon the consummation of a change in control transaction, with performance-based awards vesting at the greater of the target level or actual.

The 2024 performance-based awards are based on two equally-weighted performance measures: the three-year average growth rate of Wesco’s net income attributable to common stockholders and the three-year cumulative return on net assets. The 2025 and 2026 performance-based awards are based on two equally-weighted performance measures: the growth rate of Wesco’s earnings per share and return on net assets, both of which are measured on an annual basis as well as on a three-year cumulative basis, with each of the three years and the three-year cumulative measurement equally-weighted. The 2025 and 2026 performance-based awards also include a relative Total Stockholder Return (“TSR”) modifier that impacts the number of shares earned based on the Company's TSR over the performance period in relation to the TSR of the companies comprising the S&P MidCap 400 Index. These awards are accounted for as awards with performance conditions; compensation cost is recognized over the performance period based upon Wesco’s determination of whether it is probable that the performance targets will be achieved. The fair value of the relative TSR modifier as of each grant date for the 2025 and 2026 awards was measured using a Monte Carlo simulation.

During the three months ended March 31, 2026 and 2025, Wesco granted the following stock options, restricted stock units, and performance-based awards at the following weighted-average fair values:


	Three Months Ended
		March 31, 2026		March 31, 2025
Stock options granted		58,729		84,476
Weighted-average fair value		$	124.11	$	76.59

Restricted stock units granted		139,312		215,603
Weighted-average fair value		$	296.15	$	179.83

Performance-based awards granted		48,440		72,302
Weighted-average fair value		$	321.94	$	191.72

The fair values of stock options, as disclosed in the table above, were estimated using the following weighted-average assumptions in the respective periods:


	Three Months Ended
		March 31, 2026		March 31, 2025
Risk free interest rate		3.6	%	4.1	%
Expected life (in years)		5		5
Expected volatility		45	%	47	%
Expected dividend yield		0.68	%	1.01	%

The risk-free interest rate is based on the U.S. Treasury Daily Yield Curve rate as of the grant date. The expected life is based on historical exercise experience, the expected volatility is based on the volatility of the Company’s daily stock price over the expected life preceding the grant date of the award, and the expected dividend yield is based on the calculated yield on the Company’s common stock at the date of grant using the then current fiscal year projected dividend distribution rate.

The following table sets forth a summary of stock options and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2025	285,935	$	156.62
Granted	58,729	295.31
Exercised	(5,484)	167.14
Forfeited	—	—
Outstanding at March 31, 2026	339,180	$	180.47	7.7	$	32.9
Exercisable at March 31, 2026	202,849	$	150.42	6.6	$	25.0

For the three months ended March 31, 2026, the aggregate intrinsic value of stock options exercised during such period was $0.7 million.

The following table sets forth a summary of stock-settled stock appreciation rights and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2025	411,759	$	59.12
Granted	—	—
Exercised	(64,504)	61.57
Forfeited	(389)	42.44
Outstanding at March 31, 2026	346,866	$	58.68	3.4	$	74.6
Exercisable at March 31, 2026	346,866	$	58.68	3.4	$	74.6

For the three months ended March 31, 2026, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $14.7 million.

The following table sets forth a summary of restricted stock units and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2025	457,943	$	165.89
Granted	139,312	296.15
Vested	(153,942)	167.48
Forfeited	(3,212)	183.78
Unvested at March 31, 2026	440,101	$	206.74

The following table sets forth a summary of performance-based awards and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2025	194,635	$	171.72
Granted	48,440	321.94
Vested	—	—
Forfeited	(57,778)	171.33
Unvested at March 31, 2026	185,297	$	210.96

Wesco recognized $16.1 million and $10.2 million of non-cash stock-based compensation expense for the three months ended March 31, 2026 and 2025, respectively, which is included in selling, general and administrative expenses for such periods. As of March 31, 2026, there was $117.7 million of total unrecognized compensation expense related to unvested stock-based compensation arrangements for all awards previously made, which is expected to be recognized as follows:


For the year ending December 31,	(In millions)
Remaining 2026	$	44.4
2027	45.2
2028	24.7
2029	3.4

Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Equity [Abstract]
Stock Repurchase Program, Authorized Amount	$ 1,000.0
Common Stock, Dividends, Per Share, Declared	$ 0.500	$ 0.454
Dividends, Common Stock	$ 24.4	$ 22.1
Treasury Stock, Value, Acquired, Cost Method	$ 25.3	25.3
Dividends, Preferred Stock		$ (14.4)
Preferred Stock, Dividends, Per Share, Cash Paid		$ 0.664
Dividends Payable [Line Items]
Preferred Stock, Dividends, Per Share, Cash Paid		$ 0.664
Dividends, Preferred Stock		$ 14.4
Common Stock, Dividends, Per Share, Declared	$ 0.500	$ 0.454
Dividends, Common Stock	$ 24.4	$ 22.1
Retained Earnings [Member]
Equity [Abstract]
Dividends, Common Stock	24.4	22.1
Dividends, Preferred Stock		(14.4)
Dividends Payable [Line Items]
Dividends, Preferred Stock		14.4
Dividends, Common Stock	$ 24.4	$ 22.1
O2025Q1Dividends
Dividends Payable [Line Items]
Dividends Payable, Date Declared		Feb. 27, 2025
Dividends Payable, Date of Record		Mar. 14, 2025
Dividends Payable, Date to be Paid		Mar. 31, 2025
Dividends Payable, Date of Record		Mar. 14, 2025
Dividends Payable, Date Declared		Feb. 27, 2025
Dividends Payable, Date to be Paid		Mar. 31, 2025
O2026Q1Dividends
Dividends Payable [Line Items]
Dividends Payable, Date Declared	Feb. 26, 2026
Dividends Payable, Date of Record	Mar. 13, 2026
Dividends Payable, Date to be Paid	Mar. 31, 2026
Dividends Payable, Date of Record	Mar. 13, 2026
Dividends Payable, Date Declared	Feb. 26, 2026
Dividends Payable, Date to be Paid	Mar. 31, 2026

STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2026

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

During the three months ended March 31, 2026 and 2025, Wesco granted the following stock options, restricted stock units, and performance-based awards at the following weighted-average fair values:


	Three Months Ended
		March 31, 2026		March 31, 2025
Stock options granted		58,729		84,476
Weighted-average fair value		$	124.11	$	76.59

Restricted stock units granted		139,312		215,603
Weighted-average fair value		$	296.15	$	179.83

Performance-based awards granted		48,440		72,302
Weighted-average fair value		$	321.94	$	191.72

Share-based Payment Arrangement, Option and Stock Appreciation Rights, Activity [Table Text Block]

The following table sets forth a summary of stock-settled stock appreciation rights and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2025	411,759	$	59.12
Granted	—	—
Exercised	(64,504)	61.57
Forfeited	(389)	42.44
Outstanding at March 31, 2026	346,866	$	58.68	3.4	$	74.6
Exercisable at March 31, 2026	346,866	$	58.68	3.4	$	74.6

For the three months ended March 31, 2026, the aggregate intrinsic value of stock-settled stock appreciation rights exercised during such period was $14.7 million.

Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

The following table sets forth a summary of restricted stock units and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2025	457,943	$	165.89
Granted	139,312	296.15
Vested	(153,942)	167.48
Forfeited	(3,212)	183.78
Unvested at March 31, 2026	440,101	$	206.74

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

The following table sets forth a summary of performance-based awards and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Fair Value
Unvested at December 31, 2025	194,635	$	171.72
Granted	48,440	321.94
Vested	—	—
Forfeited	(57,778)	171.33
Unvested at March 31, 2026	185,297	$	210.96

Share-Based Payment Arrangement, Option, Activity

The following table sets forth a summary of stock options and related information for the three months ended March 31, 2026:


	Awards	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)	Aggregate Intrinsic Value (In millions)
Outstanding at December 31, 2025	285,935	$	156.62
Granted	58,729	295.31
Exercised	(5,484)	167.14
Forfeited	—	—
Outstanding at March 31, 2026	339,180	$	180.47	7.7	$	32.9
Exercisable at March 31, 2026	202,849	$	150.42	6.6	$	25.0

For the three months ended March 31, 2026, the aggregate intrinsic value of stock options exercised during such period was $0.7 million.

Stock Appreciation Rights (SARs) [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

The fair values of stock options, as disclosed in the table above, were estimated using the following weighted-average assumptions in the respective periods:


	Three Months Ended
		March 31, 2026		March 31, 2025
Risk free interest rate		3.6	%	4.1	%
Expected life (in years)		5		5
Expected volatility		45	%	47	%
Expected dividend yield		0.68	%	1.01	%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://www.xbrl.org/2003/role/disclosureRef
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Reference 28: http://www.xbrl.org/2003/role/disclosureRef
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Reference 29: http://www.xbrl.org/2003/role/disclosureRef
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Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

SUMMARY OF RESTRICTED STOCK UNITS (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based awards outstanding (in shares)	440,101		457,943
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 206.74		$ 165.89
Granted (in shares)	139,312	215,603
Granted, Weighted Average Fair Value (in dollars per share)	$ 296.15	$ 179.83
Vested (in shares)	(153,942)
Vested in Period, Weighted Average Fair Value (in dollars per share)	$ 167.48
Forfeited (in shares)	(3,212)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 183.78

SUMMARY OF PERFORMANCE-BASED AWARDS (Details) - Performance Shares [Member] - $ / shares	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested (in shares)	185,297		194,635
Granted (in shares)	48,440	72,302
Vested (in shares)	0
Forfeited (in shares)	(57,778)
Unvested, Weighted Average Fair Value (in dollars per share)	$ 210.96		$ 171.72
Granted, Weighted Average Fair Value (in dollars per share)	321.94	$ 191.72
Vested in Period, Weighted Average Fair Value (in dollars per share)	0
Forfeited in Period, Weighted Average Fair Value (in dollars per share)	$ 171.33

INCOME TAXES Income Tax Rates (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, Percent	21.80%	23.40%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	390.00%	300.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount	$ 7.7	$ 4.7

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY Statement - USD ($) $ in Millions	Total	Treasury Stock, Common [Member]	Common Class B	Common Stock	Series A Preferred Stock	AOCI Attributable to Parent [Member]	Noncontrolling Interest [Member]	Retained Earnings [Member]	Additional Paid-in Capital [Member]	Treasury Stock, Common [Member]
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,627,398
Additional capital	$ 2,051.6
Retained Earnings (Accumulated Deficit)	4,960.7
Treasury Stock, Value	(1,495.1)
Stockholders' Equity Attributable to Noncontrolling Interest	(5.2)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (547.2)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					(21,612)
Treasury Stock, Common, Shares	25,176,234
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 4,965.5
Treasury Stock, Value, Acquired, Cost Method	(25.3)	$ (25.3)								$ (25.3)
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(0.9)			$ 0.0						$ 0.9
APIC, Share-based Payment Arrangement, Recognition and Exercise	0.0
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	10.2
Treasury Stock, Shares, Acquired		153,228								153,228
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(17.1)			$ 0.0				$ 4.8	$ 12.3
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised				(257,230)						(5,053)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(89,463)
Net Income (Loss) Attributable to Parent	118.4							118.4
Dividends, Preferred Stock	(14.4)							(14.4)
Stockholders' Equity, Other							$ 0.1
Net Income (Loss) Attributable to Noncontrolling Interest	(0.1)						(0.1)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	15.9					$ 15.8
Dividends, Common Stock	(22.1)							(22.1)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	69,795,165
Additional capital	2,049.5
Retained Earnings (Accumulated Deficit)	5,037.8
Treasury Stock, Value	(1,521.3)
Stockholders' Equity Attributable to Noncontrolling Interest	(5.2)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (531.4)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					(21,612)
Treasury Stock, Common, Shares	25,334,515
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,030.1
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	70,004,866
Additional capital	1,507.3
Retained Earnings (Accumulated Deficit)	5,513.4
Treasury Stock, Value	(1,590.3)
Stockholders' Equity Attributable to Noncontrolling Interest	(5.2)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(399.5)
Treasury stock, at cost; 25,802,916 and 25,685,964 shares in 2026 and 2025, respectively	$ (1,590.3)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					0
Treasury Stock, Common, Shares	25,685,964
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,026.4
Treasury Stock, Value, Acquired, Cost Method	(25.3)	$ (25.3)								$ (25.3)
Stock Issued, Value, Stock Options Exercised, Net of Tax Benefit (Expense)	(6.1)			$ 0.0						$ 7.0
APIC, Share-based Payment Arrangement, Recognition and Exercise									0.9
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	16.1								16.1
Treasury Stock, Shares, Acquired		92,657								92,657
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(15.9)			$ 0.0				6.9	$ 9.0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised				(210,916)						(24,295)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation				(53,762)
Net Income (Loss) Attributable to Parent	153.8							153.8
Stockholders' Equity, Other								(0.1)
Net Income (Loss) Attributable to Noncontrolling Interest	0.3						$ 0.3
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(27.0)					$ (26.9)
Dividends, Common Stock	(24.4)							$ (24.4)
Common stock			$ 0.0	$ 0.7
Common Stock, Shares, Issued			4,339,431	70,162,020
Additional capital	1,515.3
Retained Earnings (Accumulated Deficit)	5,635.8
Treasury Stock, Value	(1,622.6)
Stockholders' Equity Attributable to Noncontrolling Interest	(4.9)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(426.4)
Treasury stock, at cost; 25,802,916 and 25,685,964 shares in 2026 and 2025, respectively	$ (1,622.6)
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding					$ 0.0
Preferred stock, shares issued (in shares)					0
Treasury Stock, Common, Shares	25,802,916
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,097.9

COMMITMENTS AND CONTINGENCIES	3 Months Ended
COMMITMENTS AND CONTINGENCIES	Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	From time to time, a number of lawsuits and claims have been or may be asserted against the Company relating to the conduct of its business, including litigation relating to commercial, product and employment matters. The outcome of any litigation cannot be predicted with certainty, and some lawsuits may result in a negative impact to Wesco. However, management does not believe that the ultimate outcome of any such pending matters is likely to have a material adverse effect on Wesco’s financial condition or liquidity, although the resolution in any fiscal period of one or more of these matters may have a material adverse effect on Wesco’s results of operations for that period. Recoveries related to previously recognized losses are recorded when realization is probable. Recoveries in excess of recognized losses are deferred until realized or realizable. As of March 31, 2026, the Company has a loss contingency of approximately $49.0 million related to a matter in Other current liabilities, along with a corresponding insurance recovery receivable of $48.5 million in Other accounts receivable on the unaudited Condensed Consolidated Balance Sheet. As a result, the Company does not expect to incur a loss other than for the insurance deductible amount, which is not material to the unaudited Condensed Consolidated Financial Statements. On February 20, 2026, the U.S. Supreme Court ruled that tariffs previously imposed under the International Emergency Economic Powers Act (“IEEPA”) were invalid. The availability, timing, amount, and process for any potential refunds previously paid by the Company is uncertain and subject to further developments. Accordingly, the Company cannot reasonably estimate any potential financial impact at this time, and no related amounts have been recorded in the unaudited Condensed Consolidated Financial Statements as of March 31, 2026. The Company continues to monitor developments and evaluate potential impacts on its financial condition and results of operations.

Segment Reporting (Tables)	3 Months Ended
Segment Reporting (Tables)	Mar. 31, 2026
Segment Reporting [Abstract]
Segment Reporting

- Definition

Tabular disclosure of segment reporting. Includes, but is not limited to, reconciliation of reportable segment amount to corresponding consolidated total.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-34

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26B

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26A

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 25
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-25

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-15

+ Details

REVENUE Shipping and Handling Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Cost of goods sold	$ 4,788.3	$ 4,218.1
Selling, general and administrative expense	947.6	836.3
Shipping and Handling Associated with Revenue
Selling, general and administrative expense	$ 88.8
Shipping and Handling [Member]
Selling, general and administrative expense		$ 76.5

- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References + Details

- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References + Details

Summary of Non-Qualified Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 58.68		$ 59.12
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	0
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	61.57
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	42.44
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 58.68
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 14.7
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	346,866
Weighted Average Remaining Contractual Term, Exercisable (in years)	3 years 4 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 74.6
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross	58,729	84,476
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	(5,484)
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 180.47		$ 156.62
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	295.31
Weighted Average Exercise Price, Exercises in Period (in dollars per share)	167.14
Weighted Average Exercise Price, Forfeitures in Period (in dollars per share)	0
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 150.42
Weighted Average Remaining Contractual Term, Outstanding (in years)	7 years 8 months 12 days
Aggregate Intrinsic Value, Outstanding	$ 32.9
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 0.7
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number	339,180		285,935
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	202,849
Weighted Average Remaining Contractual Term, Exercisable (in years)	6 years 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 25.0

ORGANIZATION Organization (Details)	3 Months Ended
ORGANIZATION Organization (Details)	Mar. 31, 2026 distribution_centers
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of Reportable Segments	3

ACCOUNTING POLICIES	3 Months Ended
ACCOUNTING POLICIES	Mar. 31, 2026
Accounting Policies [Abstract]
ACCOUNTING POLICIES	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of Wesco have been prepared in accordance with Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). The unaudited condensed consolidated financial information should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto included in WESCO International, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the SEC on February 13, 2026. The Condensed Consolidated Balance Sheet at December 31, 2025 was derived from the audited Consolidated Financial Statements as of that date, but does not include all the disclosures required by accounting principles generally accepted in the United States of America. The unaudited Condensed Consolidated Balance Sheet as of March 31, 2026, the unaudited Condensed Consolidated Statements of Income and Comprehensive Income, the unaudited Condensed Consolidated Statements of Equity, and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2026 and 2025, respectively, in the opinion of management, have been prepared on the same basis as the audited Consolidated Financial Statements and include all adjustments necessary for the fair statement of the results of the interim periods presented herein. All adjustments reflected in the unaudited condensed consolidated financial information are of a normal recurring nature unless indicated. The results for the interim periods presented herein are not necessarily indicative of the results to be expected for the full year. Reclassifications The unaudited Condensed Consolidated Statement of Cash Flows for the three months ended March 31, 2025, includes certain reclassifications to previously reported amounts to conform to the current period's presentation. Such reclassifications had no impact on the totals of operating, investing and financing cash flow activities. Recently Issued Accounting Standards In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which is intended to enhance expense disclosures, primarily by requiring disclosure of disaggregated information about certain income statement expense line items on an annual and interim basis. The amendments in this ASU are effective for fiscal years beginning after December 15, 2026 and interim periods within fiscal years beginning after December 15, 2027. The amendments in this ASU should be applied prospectively; however, retrospective application is permitted. Management is currently evaluating the impact that this accounting standard will have on its consolidated financial statements and notes thereto. In September 2025, the FASB issued ASU 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which is intended to modernize and simplify the guidance for capitalizing costs related to internal-use software by removing the stage-based approach and aligning the disclosure requirements with those for other long-lived assets. The amendments in this ASU are effective for annual periods beginning after December 15, 2027 and may be applied prospectively, retrospectively, or using a modified prospective approach. Early adoption is permitted. Management is currently evaluating the timing of the adoption of this accounting standard and the impact that it will have on its consolidated financial statements and notes thereto. Other pronouncements issued by the FASB or other authoritative accounting standards groups with future effective dates are either not applicable or are not expected to be material to Wesco’s financial position, results of operations or cash flows.
Reclassifications	Reclassifications The unaudited Condensed Consolidated Statement of Cash Flows for the three months ended March 31, 2025, includes certain reclassifications to previously reported amounts to conform to the current period's presentation. Such reclassifications had no impact on the totals of operating, investing and financing cash flow activities.

CONSOLIDATED BALANCE SHEETS (parenthetical items) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Total accounts receivable, net of allowance for expected credit losses	$ 67.8	$ 63.6
Accumulated depreciation	649.3	626.1
Long-term debt, net of debt discount and debt issuance costs	$ 63.6	$ 48.0
Treasury Stock, Common, Shares	25,802,916	25,685,964
Assets, Current	$ 9,953.6	$ 9,456.2
Assets	16,964.7	16,494.9
Liabilities, Current	4,688.2	4,296.8
Liabilities	11,866.8	11,468.5
Total stockholders' equity	5,102.8	5,031.6
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	5,097.9	5,026.4
Liabilities and Equity	$ 16,964.7	$ 16,494.9
Preferred Stock
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares outstanding (in shares)	0	0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Series A Preferred Stock
Preferred stock, shares issued (in shares)	0	0
Common Stock
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	210,000,000	210,000,000
Common stock, shares, issued (in shares)	70,162,020	70,004,866
Common stock, shares outstanding (in shares)	48,698,535	48,658,333
Common Class B
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares, issued (in shares)	4,339,431	4,339,431
Common stock, shares outstanding (in shares)	0	0

SCHEDULE OF SHARE-BASED PAYMENT AWARD, VALUATION ASSUMPTIONS (Details) - Share-based Payment Arrangement, Option	3 Months Ended
	Mar. 31, 2026 Rate	Mar. 31, 2025 Rate
Share-Based Payment Arrangement [Abstract]
WESCO expected volatility	45.00%	47.00%
Risk free interest rate	3.60%	4.10%
Expected life (in years)	5 years	5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.68%	1.01%
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free interest rate	3.60%	4.10%
Expected life (in years)	5 years	5 years
WESCO expected volatility	45.00%	47.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate	0.68%	1.01%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

COVER PAGE - shares	3 Months Ended
COVER PAGE - shares	Mar. 31, 2026	Apr. 29, 2026
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2026
Document Transition Report	false
Entity File Number	001-14989
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	25-1723342
Entity Address, Address Line One	225 West Station Square DriveSuite 700
Entity Address, City or Town	Pittsburgh,
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15219
City Area Code	412
Local Phone Number	454-2200
Title of 12(b) Security	Common Stock, par value $.01 per share
Trading Symbol	WCC
Security Exchange Name	NYSE
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Registrant Name	WESCO International, Inc.
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Central Index Key	0000929008
Entity Common Stock, Shares Outstanding		48,704,892
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $.01 per share
Trading Symbol	WCC
Security Exchange Name	NYSE

INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended
INCOME TAXES (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Income Tax Contingency [Line Items]
Effective tax rate	21.80%	23.40%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount	$ 7.7	$ 4.7
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	390.00%	300.00%
Investment Tax Credit	$ 1.0	$ 53.3
Income Tax Examination, Description	In October 2021, one of the Company’s Mexican affiliates received a tax assessment from the Mexican tax authorities related to its 2012 income tax return which was approximately $33.4 million as of December 31, 2025. The Company believed the assessment was without merit and the Company's Mexican affiliate filed an annulment lawsuit in the Mexican Federal Court of Administrative Justice (the “Court”). The Company expected to prevail in this litigation and, accordingly, did not recognize a liability for this assessment in its Consolidated Financial Statements. On April 23, 2026, the Company received the written decision of the Court. The Company is still evaluating the Court's decision. To the extent that the decision is unfavorable to the Company's Mexican affiliate, it will file an appeal for constitutional review of the lower court decision with the Mexican Federal Collegiate Circuit Court. The Company maintains that it ultimately expects to prevail upon final resolution of the matter.

FAIR VALUE (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative, Notional Amount	$ 322.5	$ 286.3
Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Fair Value	5,424.4	4,004.2
Long-term Debt	$ 5,372.2	$ 3,871.9

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

+ Details

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation	$ 696.6	$ 604.8
Accounts Receivable, after Allowance for Credit Loss, Current	4,273.1	4,069.6
Accounts and Other Receivables, Net, Current	478.9	522.4
Inventories, net	4,213.1	4,008.8
Prepaid expenses and other current assets	291.9	250.6
Assets, Current	9,953.6	9,456.2
Property, buildings and equipment, net of accumulated depreciation of $229,041 and $213,758 in 2014 and 2013, respectively	476.0	466.8
Operating Lease, Right-of-Use Asset	889.0	888.3
Intangible assets, net	1,745.9	1,769.2
Goodwill	3,331.6	3,343.4
Deferred Income Tax Assets, Net	48.4	45.7
Other assets	520.2	525.3
Assets	16,964.7	16,494.9
Accounts payable	3,470.5	3,030.5
Accrued payroll and benefit costs	203.5	283.0
Current portion of long-term debt	22.8	25.0
Other Liabilities, Current	991.4	958.3
Liabilities, Current	4,688.2	4,296.8
Total long-term debt	5,738.1	5,756.4
Operating Lease, Liability, Noncurrent	749.7	752.2
Deferred Income Tax Liabilities, Net	455.8	427.2
Other Liabilities, Noncurrent	235.0	235.9
Liabilities	11,866.8	11,468.5
Commitments and Contingencies
Additional capital	1,515.3	1,507.3
Retained earnings	5,635.8	5,513.4
Treasury stock, at cost; 25,802,916 and 25,685,964 shares in 2026 and 2025, respectively	(1,622.6)	(1,590.3)
Accumulated other comprehensive income	(426.4)	(399.5)
Total WESCO International, Inc. equity	5,102.8	5,031.6
Noncontrolling interest	(4.9)	(5.2)
Total equity	5,097.9	5,026.4
Liabilities and Equity	16,964.7	16,494.9
Preferred Stock
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	0.0	0.0
Series A Preferred Stock
Preferred stock, $.01 par value; 20,000,000 shares authorized, no shares issued or outstanding	0.0	0.0
Common Stock
Common stock	0.7	0.7
Common Class B
Common stock	$ 0.0	$ 0.0

Business Combinations, Asset Acquisitions, and Joint Venture Formation	3 Months Ended
	Mar. 31, 2026
Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]
Business Combination	Industrial Software Solutions On January 2, 2025, the Company acquired 100% of the equity securities of Industrial Software Solutions I, Inc. and Industrial Software Solutions ULC (collectively, “ISS”), an industrial automation consulting company, software distributor, and AVEVA Select Partner, for total cash consideration of $36.3 million, net of cash acquired. The assets acquired primarily included distribution agreement and customer relationship intangible assets, with fair values of $10.6 million and $5.0 million, respectively, with the excess of $20.1 million primarily allocated to Goodwill in the Company’s EES reportable segment.

- Definition

The entire disclosure for business combination.

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Segment Reporting - Capital Expenditures (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	$ (0.4)	$ 0.2
Payments for (Proceeds from) Productive Assets	23.4	20.4
Operating Segments
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	19.5	15.1
Payments for (Proceeds from) Productive Assets	6.2	8.2
EES
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	6.8	4.4
Payments for (Proceeds from) Productive Assets	1.3	1.2
CSS
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	13.1	10.9
Payments for (Proceeds from) Productive Assets	1.5	1.6
UBS
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	(0.4)	(0.2)
Payments for (Proceeds from) Productive Assets	3.4	5.4
Corporate Segment
Segment Reporting [Line Items]
Other Nonoperating Income (Expense)	(19.9)	(14.9)
Payments for (Proceeds from) Productive Assets	$ 17.2	$ 12.2

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

REVENUE Revenue, Performance Obligation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Revenue from Contract with Customer [Abstract]
Cost of goods sold	$ 4,788.3	$ 4,218.1

- Definition

+ References + Details

GOODWILL (Tables)

3 Months Ended

Mar. 31, 2026

Goodwill [Line Items]

Goodwill [Table Text Block]


	EES		CSS		UBS		Total
	(In millions)
Beginning balance, January 1, 2026	$	843.8	$	1,354.1	$	1,145.5	$	3,343.4


Foreign currency exchange rate changes	(7.5)		(0.7)		(3.6)		(11.8)
Ending balance, March 31, 2026	$	836.3	$	1,353.4	$	1,141.9	$	3,331.6

Intangible Asset, Finite-Lived

The components of intangible assets are as follows:


		As of
		March 31, 2026						December 31, 2025
	Life (in years)	Gross Carrying Amount(1)		Accumulated Amortization(1)		Net Carrying Amount		Gross Carrying Amount(1)		Accumulated Amortization(1)		Net Carrying Amount
Intangible assets:		(In millions)
Trademarks	Indefinite	$	791.0	$	—	$	791.0	$	791.6	$	—	$	791.6
Customer relationships	9 - 20	1,504.9		(572.7)		932.2		1,523.6		(570.2)		953.4
Distribution agreements	8	10.7		(1.6)		9.1		10.7		(1.3)		9.4
Trademarks	5 and 12	15.5		(14.6)		0.9		15.5		(14.0)		1.5
Software	7	16.0		(4.0)		12.0		16.0		(3.4)		12.6
Technology know-how	5	0.9		(0.2)		0.7		0.9		(0.2)		0.7
		$	2,339.0	$	(593.1)	$	1,745.9	$	2,358.3	$	(589.1)	$	1,769.2

(1) Excludes the original cost and related accumulated amortization of fully-amortized intangible assets.

Intangible Asset, Finite-Lived, and Capitalized Cost, Software to be Sold, Leased, or Marketed, Estimated Amortization Expense

The following table sets forth the remaining estimated amortization expense for intangible assets for the next five years and thereafter:


For the year ending December 31,	(In millions)
Remaining 2026	$	63.8
2027	83.2
2028	81.6
2029	80.5
2030	74.3
Thereafter	571.5
Total	$	954.9

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Tabular disclosure of goodwill.

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+ Details

Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Millions		3 Months Ended
	Jan. 02, 2025	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Asset Acquisition [Line Items]
Goodwill		$ 3,331.6		$ 3,343.4
Cash paid for acquisition		$ 0.0	$ 35.2
Industrial Software Solutions
Asset Acquisition [Line Items]
Business Combination, Effective Date of Acquisition	Jan. 02, 2025
Business Combination, Description of Acquiree		an industrial automation consulting company, software distributor, and AVEVA Select Partner
Total purchase consideration	$ 36.3
Business Combination, Recognized Asset Acquired, Distribution Agreement intangible asset	10.6
Business Combination, Recognized Asset Acquired, Customer relationship intangible asset	5.0
Goodwill	$ 20.1

- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References

+ Details

REVENUE Variable Consideration (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Revenue, Methods, Inputs, and Assumptions Used [Abstract]
Revenue, Variable Consideration Constraint Increase (Decrease)	$ 115.2	$ 113.0

REVENUE (Details) - USD ($) $ in Millions	3 Months Ended
REVENUE (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Disaggregation of Revenue [Line Items]
Deferred Revenue	$ 167.0		$ 151.4	$ 141.8
Revenue from Contract with Customer, Excluding Assessed Tax	6,080.1	$ 5,343.7
Cost of goods sold	4,788.3	4,218.1
Contract with Customer, Refund Liability	37.4		$ 33.7
EES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,244.2	2,065.3
CSS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,478.9	2,000.3
UBS
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,357.0	1,278.1
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,504.6	3,974.6
CANADA
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	827.1	712.8
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 748.4	$ 656.3

ACCOUNTING POLICIES (Details) - USD ($) $ in Millions	3 Months Ended
ACCOUNTING POLICIES (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Accounting Policies [Abstract]
Dividends, Preferred Stock		$ 14.4
Dividends, Common Stock	$ (24.4)	(22.1)
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation	$ 696.6	$ 681.6	$ 604.8	$ 702.6

Segment Reporting	3 Months Ended
Segment Reporting	Mar. 31, 2026
Segment Reporting [Abstract]
Segment Reporting	13. BUSINESS SEGMENTS The Company has operating segments comprising three strategic business units: EES, CSS and UBS. These operating segments are equivalent to the Company’s reportable segments. The President and Chief Executive Officer serves as the Company’s Chief Operating Decision Maker (“CODM”). The CODM evaluates the performance of the Company’s reportable segments based on Adjusted earnings before interest, taxes, depreciation and amortization (“Adjusted EBITDA”), which is the Company’s measure of segment profit or loss. The Company incurs corporate costs primarily related to treasury, tax, information technology, finance, legal and other centralized functions. The Company also has various corporate assets. Segment assets may not include jointly used assets, but segment results include allocations related to those assets. Interest expense and other non-operating items are either not allocated to the segments or reviewed on a segment basis. Corporate expenses and assets not directly identifiable with a reportable segment are reported in the tables below to reconcile the reportable segments to the Consolidated Financial Statements.

- Definition

The entire disclosure for segment reporting.

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+ Details

REVENUE (Notes)

3 Months Ended

Mar. 31, 2026

Revenue from Contract with Customer [Abstract]

Revenue from Contract with Customer

3. REVENUE

Wesco distributes products and provides services to customers globally in various end markets within its business segments. The segments operate in the United States, Canada and various other countries.

The following table disaggregates Wesco’s Net sales by geography for the periods presented:


	Three Months Ended
	March 31
(In millions)	2026		2025
United States	$	4,504.6	$	3,974.6
Canada	827.1		712.8
Other International(1)	748.4		656.3
Total by geography(2)	$	6,080.1	$	5,343.7

(1) No individual country's net sales are greater than 10% of total Net sales.

(2) Wesco attributes revenues from external customers to individual countries on the basis of point of sale.

Due to the terms of certain contractual arrangements, Wesco bills or receives payment from its customers in advance of satisfying the respective performance obligation. Such advance billings or payments are recorded as deferred revenue and recognized as revenue when the performance obligation has been satisfied and control has transferred to the customer, which is generally upon shipment. Revenue associated with these arrangements is generally recognized within a year or less from the date of the advance billing or payment receipt. At March 31, 2026, December 31, 2025 and December 31, 2024, $167.0 million, $151.4 million and $141.8 million, respectively, of deferred revenue was recorded as a component of Other current liabilities in the Condensed Consolidated Balance Sheets. The Company recognized $51.2 million and $57.4 million of revenue during the three months ended March 31, 2026 and 2025, respectively, that was included in the deferred revenue balance as of December 31, 2025 and 2024, respectively.

Wesco’s revenues are adjusted for variable consideration, which includes customer volume rebates, returns and discounts. Wesco measures variable consideration by estimating expected outcomes using analysis and inputs based upon historical data, as well as current and forecasted information. Variable consideration is reviewed by management on a monthly basis and revenue is adjusted as necessary. Variable consideration reduced revenue by approximately $115.2 million and $113.0 million, for the three months ended March 31, 2026 and 2025, respectively. As of March 31, 2026 and December 31, 2025, the Company's estimated product return obligation was $37.4 million and $33.7 million, respectively.

Billings to customers for shipping and handling are recognized in Net sales. Wesco has elected to recognize shipping and handling costs as a fulfillment cost. Shipping and handling costs recorded as a component of Selling, general and administrative expenses totaled $88.8 million and $76.5 million for the three months ended March 31, 2026 and 2025, respectively.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

EARNINGS PER SHARE

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

EARNINGS PER SHARE

Basic earnings per share is computed by dividing net income attributable to common stockholders by the weighted-average number of common shares outstanding during the periods. Diluted earnings per share is computed by dividing net income attributable to common stockholders by the weighted-average common shares and common share equivalents outstanding during the periods. The dilutive effect of common share equivalents is considered in the diluted earnings per share computation using the treasury stock method, which includes consideration of equity awards.

The following table sets forth the computation of Basic and Diluted earnings per share for the periods presented:


	Three Months Ended
	March 31
(In millions, except per share data)		2026		2025
Net income attributable to WESCO International, Inc.		$	153.8	$	118.4

Less: Preferred stock dividends		—		14.4
Net income attributable to common stockholders		$	153.8	$	104.0
Weighted-average common shares outstanding used in computing basic earnings per share		48.7		48.8
Common shares issuable upon exercise of dilutive equity awards		0.8		0.8
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share		49.5		49.6
Earnings per share attributable to common stockholders
Basic		$	3.16	$	2.13
Diluted		$	3.11	$	2.10

The computation of diluted earnings per share attributable to common stockholders excludes stock-based awards that would have had an antidilutive effect on earnings per share. For the three months ended March 31, 2026 and 2025, there were approximately 0.1 million and 0.5 million antidilutive shares, respectively.

SCHEDULE OF DEBT (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Finance lease obligations	$ 76.8	$ 67.3
Total debt	5,821.7	5,826.3
Unamortized debt issuance costs	(60.8)	(44.9)
Short-term debt and current portion of long-term debt	(22.8)	(25.0)
Total long-term debt	5,738.1	5,756.4
Foreign Line of Credit
Debt Instrument [Line Items]
Long-term Debt	1.2	5.6
Accounts Receivable Securitization Facility
Debt Instrument [Line Items]
Long-term Debt	120.0	1,300.0
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Debt	251.5	581.5
7.250% Senior Notes due 2028
Debt Instrument [Line Items]
Long-term Debt	1,322.2	1,321.9
Debt Instrument, Unamortized Discount	2.8	3.1
6.375% Senior Notes due 2029
Debt Instrument [Line Items]
Long-term Debt	900.0	900.0
6.625% Senior Notes due 2032
Debt Instrument [Line Items]
Long-term Debt	850.0	850.0
6.375% Senior Notes due 2033
Debt Instrument [Line Items]
Long-term Debt	800.0	800.0
5.250% Senior Notes due 2031
Debt Instrument [Line Items]
Long-term Debt	650.0	0.0
5.500% Senior Notes due 2034
Debt Instrument [Line Items]
Long-term Debt	$ 850.0	$ 0.0

COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	Mar. 31, 2026 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Loss Contingency, Accrual, Current	$ 49.0
Insurance Settlements Receivable, Current	$ 48.5

GOODWILL (Details) - USD ($) $ in Millions	3 Months Ended
GOODWILL (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Goodwill [Line Items]
Goodwill	$ 3,331.6		$ 3,343.4
Goodwill, Foreign Currency Translation, Gain (Loss)	(11.8)
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Accumulated Amortization	(593.1)		(589.1)
Intangible Asset, Excluding Goodwill, before Accumulated Amortization	2,339.0		2,358.3
Intangible assets, net	1,745.9		1,769.2
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One	63.8
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two	83.2
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three	81.6
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four	80.5
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Five	74.3
Intangible Asset, Finite-Lived, Estimated Amortization Expense, after Year Five	571.5
Finite-Lived Intangible Asset, Expected Amortization, Total	954.9
Intangible Asset, Finite-Lived, Amortization Expense	21.8	$ 22.2
Intangible Asset, Finite-Lived, Amortization Expense	21.8	$ 22.2
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three	81.6
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four	80.5
Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Five	74.3
Intangible Asset, Finite-Lived, Estimated Amortization Expense, after Year Five	571.5
Trademarks [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, before Accumulated Amortization	15.5		15.5
Intangible Asset, Finite-Lived, Accumulated Amortization	(14.6)		(14.0)
Intangible Asset, Finite-Lived, after Accumulated Amortization	0.9		1.5
Customer Relationships [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, before Accumulated Amortization	1,504.9		1,523.6
Intangible Asset, Finite-Lived, Accumulated Amortization	(572.7)		(570.2)
Intangible Asset, Finite-Lived, after Accumulated Amortization	$ 932.2		953.4
Distribution Rights [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	8 years
Intangible Asset, Finite-Lived, before Accumulated Amortization	$ 10.7		10.7
Intangible Asset, Finite-Lived, Accumulated Amortization	(1.6)		(1.3)
Intangible Asset, Finite-Lived, after Accumulated Amortization	$ 9.1		9.4
Technology-Based Intangible Assets
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	5 years
Intangible Asset, Finite-Lived, before Accumulated Amortization	$ 0.9		0.9
Intangible Asset, Finite-Lived, Accumulated Amortization	(0.2)		(0.2)
Intangible Asset, Finite-Lived, after Accumulated Amortization	$ 0.7		0.7
Software, Purchased
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	7 years
Intangible Asset, Finite-Lived, before Accumulated Amortization	$ 16.0		16.0
Intangible Asset, Finite-Lived, Accumulated Amortization	(4.0)		(3.4)
Intangible Asset, Finite-Lived, after Accumulated Amortization	$ 12.0		12.6
Minimum [Member] \| Trademarks [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	5 years
Minimum [Member] \| Customer Relationships [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	9 years
Maximum [Member] \| Trademarks [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	12 years
Maximum [Member] \| Customer Relationships [Member]
Intangible Asset, Finite-Lived [Line Items]
Intangible Asset, Finite-Lived, Useful Life	20 years
EES
Goodwill [Line Items]
Goodwill	$ 836.3		843.8
Goodwill, Foreign Currency Translation, Gain (Loss)	(7.5)
CSS
Goodwill [Line Items]
Goodwill	1,353.4		1,354.1
Goodwill, Foreign Currency Translation, Gain (Loss)	(0.7)
UBS
Goodwill [Line Items]
Goodwill	1,141.9		1,145.5
Goodwill, Foreign Currency Translation, Gain (Loss)	(3.6)
Trademarks [Member]
Intangible Asset, Finite-Lived [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 791.0		$ 791.6

STOCK-BASED COMPENSATION (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended	12 Months Ended
STOCK-BASED COMPENSATION (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2026	Dec. 31, 2029	Dec. 31, 2028	Dec. 31, 2027
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 16.1	$ 10.2
Total unrecognized compensation cost	$ 117.7
Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 44.4	$ 3.4	$ 24.7	$ 45.2

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

EARNINGS PER SHARE (Tables)

3 Months Ended

Mar. 31, 2026

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The following table sets forth the computation of Basic and Diluted earnings per share for the periods presented:


	Three Months Ended
	March 31
(In millions, except per share data)		2026		2025
Net income attributable to WESCO International, Inc.		$	153.8	$	118.4

Less: Preferred stock dividends		—		14.4
Net income attributable to common stockholders		$	153.8	$	104.0
Weighted-average common shares outstanding used in computing basic earnings per share		48.7		48.8
Common shares issuable upon exercise of dilutive equity awards		0.8		0.8
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share		49.5		49.6
Earnings per share attributable to common stockholders
Basic		$	3.16	$	2.13
Diluted		$	3.11	$	2.10

ACCOUNTING POLICIES (Policies)	3 Months Ended
ACCOUNTING POLICIES (Policies)	Mar. 31, 2026
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements of Wesco have been prepared in accordance with Rule 10-01 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). The unaudited condensed consolidated financial information should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto included in WESCO International, Inc.’s Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the SEC on February 13, 2026. The Condensed Consolidated Balance Sheet at December 31, 2025 was derived from the audited Consolidated Financial Statements as of that date, but does not include all the disclosures required by accounting principles generally accepted in the United States of America. The unaudited Condensed Consolidated Balance Sheet as of March 31, 2026, the unaudited Condensed Consolidated Statements of Income and Comprehensive Income, the unaudited Condensed Consolidated Statements of Equity, and the unaudited Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2026 and 2025, respectively, in the opinion of management, have been prepared on the same basis as the audited Consolidated Financial Statements and include all adjustments necessary for the fair statement of the results of the interim periods presented herein. All adjustments reflected in the unaudited condensed consolidated financial information are of a normal recurring nature unless indicated. The results for the interim periods presented herein are not necessarily indicative of the results to be expected for the full year.
New Accounting Pronouncements and Changes in Accounting Principles [Text Block]	Recently Issued Accounting Standards In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which is intended to enhance expense disclosures, primarily by requiring disclosure of disaggregated information about certain income statement expense line items on an annual and interim basis. The amendments in this ASU are effective for fiscal years beginning after December 15, 2026 and interim periods within fiscal years beginning after December 15, 2027. The amendments in this ASU should be applied prospectively; however, retrospective application is permitted. Management is currently evaluating the impact that this accounting standard will have on its consolidated financial statements and notes thereto. In September 2025, the FASB issued ASU 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which is intended to modernize and simplify the guidance for capitalizing costs related to internal-use software by removing the stage-based approach and aligning the disclosure requirements with those for other long-lived assets. The amendments in this ASU are effective for annual periods beginning after December 15, 2027 and may be applied prospectively, retrospectively, or using a modified prospective approach. Early adoption is permitted. Management is currently evaluating the timing of the adoption of this accounting standard and the impact that it will have on its consolidated financial statements and notes thereto. Other pronouncements issued by the FASB or other authoritative accounting standards groups with future effective dates are either not applicable or are not expected to be material to Wesco’s financial position, results of operations or cash flows.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-1

Reference 38: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 250
-Publisher FASB
-URI https://asc.fasb.org/250/tableOfContent

Reference 39: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480175/815-40-65-1

+ Details