X0407 4 2023-03-31 0 0000929008 WESCO INTERNATIONAL INC WCC 0001428491 Lazzaris Diane 225 WEST STATION SQUARE DRIVE SUITE 700 PITTSBURGH PA 15219 0 1 0 0 EVP and General Counsel 0 Common Stock 2023-03-31 4 A 0 38.8613 0.00 A 51348.8613 D Represents dividend equivalent rights ("DERs") in connection with the Issuer's quarterly dividend and accrued to the Reporting Person on restricted stock units held by the Reporting Person. These DERs vest on the same schedules as the underlying awards. /s/ Michele Nelson, as Attorney-in-Fact 2023-04-04