MCKESSON CORP

Our Chief Executive Officer and our Chief Financial Officer, with the participation of other members of the Company’s management, have evaluated the effectiveness of the Company’s “disclosure controls and procedures” (as such term is defined in Exchange Act Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of the end of the period covered by this quarterly report, and our Chief Executive Officer and our Chief Financial Officer have concluded that our disclosure controls and procedures are effective based on their evaluation of these controls and procedures as required by paragraph (b) of Exchange Act Rules 13a-15 or 15d-15.

There were no changes in our “internal control over financial reporting” (as such term is defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) identified in connection with the evaluation required by paragraph (d) of Exchange Act Rules 13a-15 and 15d-15 that occurred during the three months ended June 30, 2025 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.