Company: WCC
Filing Date: 2025-06-17
Form Type: 11-K
Source: 0000929008-25-000018
Chunk: 2

Company: WESCO INTERNATIONAL INC
Filing Date: 2025-06-17
Form: 11-K
Chunk 2
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#### Supplemental Information
The supplemental information in the accompanying schedule of assets (held at end of year) as of December 31, 2024, has been subjected to audit procedures performed in conjunction with the audit of the Plan’s financial statements. The supplemental information is presented for the purpose of additional analysis and is not a required part of the financial statements but included supplemental information required by the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. The supplemental information is the responsibility of the Plan’s management. Our audit procedures included determining whether the supplemental information reconciles to the financial statements or the underlying accounting and other records, as applicable, and performing procedures to test the completeness and accuracy of the information presented in the supplemental information. In forming our opinion on the supplemental information, we evaluated whether the supplemental information, including its form and content, is presented in conformity with the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. In our opinion, the supplemental information is fairly stated, in all material respects, in relation to the financial statements as a whole.

/s/ BDO USA, P.C.

We have served as the Plan’s auditor since 2014.

Troy, Michigan

June 17, 2025

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| WESCO Distribution, Inc.                        |
| Retirement Savings Plan                         |
| Statements of Net Assets Available for Benefits |

| Investments                                 |     | As of        
 December 31, 
 2024         |               |     | 2023 |               |
|:--------------------------------------------|:----|:-------------|--------------:|:----|:-----|--------------:|
| Investments at fair value (Notes 2 and 4)   |     | $            | 1,796,948,887 |     | $    | 1,592,223,309 |
| Investment at contract value (Note 5)       |     |              |    92,795,035 |     |      |   100,466,763 |
| Total investments                           |     |              | 1,889,743,922 |     |      | 1,692,690,072 |
| Receivables                                 |     |              |               |     |      |               |
| Employer contributions (Note 1)             |     |              |     3,084,727 |     |      |     3