Page 1

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 FORM 10 - K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended March 31 , 2021 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number : 1-13252 MCKESSON MCKESSON CORPORATION ( Exact name of registrant as specified in its charter ) Delaware ( State or other jurisdiction of incorporation or organization ) ( Title of each class ) Common stock , $ 0.01 par value 0.625 % Notes due 2021 1.500 % Notes due 2025 1.625 % Notes due 2026 3.125 % Notes due 2029 Large accelerated filer Non - accelerated filer 6555 State Hwy 161 , Irving , TX 75039 ( Address of principal executive offices , including zip code ) ( 972 ) 446-4800 ( Registrant's telephone number , including area code ) Securities registered pursuant to Section 12 ( b ) of the Act : ( Trading Symbol ) MCK MCK21A MCK25 MCK26 MCK29 X Securities registered pursuant to Section 12 ( g ) of the Act : None Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes > NO □ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15 ( d ) of the Act . Yes No 区 Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes No □ Indicate by check mark whether the registrant has submitted electronically , every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( §232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes > No □ ☐ ( I.R.S. Employer Identification No. ) Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , " " accelerated filer , " " smaller reporting company " and " emerging growth company " in Rule 12b - 2 of the Exchange Act . ( Check one ) : 94-3207296 ( Name of each exchange on which registered ) New York Stock Exchange New York Stock Exchange New York Stock Exchange New York Stock Exchange New York Stock Exchange Number of shares of common stock outstanding on April 30 , 2021 : 158,186,277 Accelerated filer Smaller reporting company Emerging growth company If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404 ( b ) of the Sarbanes - Oxley Act ( 15 U.S.C. 7262 ( b ) ) by the registered public accounting firm that prepared or issued its audit report . Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes No The aggregate market value of the voting and non - voting common equity held by non - affiliates of the registrant , computed by reference to the closing price as of the last business day of the registrant's most recently completed second fiscal quarter , September 30 , 2020 , was approximately $ 23.9 billion . DOCUMENTS INCORPORATED BY REFERENCE 0 0 Portions of the registrant's Proxy Statement for its 2021 Annual Meeting of Stockholders are incorporated by reference into Part III of this Annual Report on Form 10 - K .