WESCO INTERNATIONAL INC

Conclusion Regarding the Effectiveness of Disclosure Controls and Procedures

Under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, we conducted an evaluation of our disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)). Based on this evaluation, our principal executive officer and our principal financial officer concluded that our disclosure controls and procedures were effective as of the end of the period covered by this report.

Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting as such term is defined in Exchange Act Rules 13a-15(f) and 15d-15(f). Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the updated framework in Internal Control — Integrated Framework (2013) (2013 Framework) issued by the Committee of Sponsoring Organizations of the Treadway Commission on May 14, 2013. Based on our evaluation under the 2013 Framework, our management concluded that our internal control over financial reporting was effective as of December 31, 2024.

As permitted by Securities and Exchange Commission guidance, management excluded Ascent, LLC from its assessment of internal control over financial reporting, which was acquired on December 5, 2024, and accounted for less than 1% of consolidated total assets and less than 1% of consolidated net sales as of and for the year ended December 31, 2024.

The effectiveness of the Company’s internal control over financial reporting as of December 31, 2024 has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report, which is included herein.

Changes in Internal Control Over Financial Reporting

During the last fiscal quarter of 2024, there were no changes in the Company’s internal control over financial reporting identified in connection with management’s evaluation of the effectiveness of the Company’s internal control over financial reporting that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.