Exhibit 5.1

October 1, 2020

Best Buy Co., Inc.

7601 Penn Avenue South

Richfield, Minnesota 55423

Ladies and Gentlemen:

We have acted as counsel to Best Buy Co., Inc., a Minnesota corporation (the “Company”), in connection with the preparation and filing with the Securities and Exchange Commission (the “Commission”) of the Company’s prospectus supplement dated September 29, 2020 (the “Prospectus Supplement”) to the prospectus dated September 28, 2020 relating to the registration statement on Form S-3ASR (File No. 333-249084) (the “Registration Statement”) filed by the Company with the Commission on September 28, 2020 with regard to the offer and sale by the Company of $650,000,000 of the Company’s 1.950% notes due 2030 (the “Securities”) pursuant to an Underwriting Agreement dated September 29, 2020 (the “Underwriting Agreement”) between the Company and the several underwriters named therein, for which Citigroup Global Markets Inc., Goldman Sachs & Co. LLC and J.P. Morgan Securities LLC acted as representatives. The Securities will be issued pursuant to the indenture dated as of March 11, 2011 (the “Base Indenture”), as supplemented by the fourth supplemental indenture thereto (the “Fourth Supplemental Indenture” and, together, with the “Base Indenture”, the “Indenture”) dated as of October 1, 2020, between the Company and U.S. Bank National Association, as successor trustee (the “Trustee”).

We have examined such documents and have reviewed such questions of law as we have considered necessary or appropriate for the purposes of our opinion set forth below. In rendering our opinion set forth below, we have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures and the conformity to authentic originals of all documents submitted to us as copies. We have also assumed the legal capacity for all purposes relevant hereto of all natural persons and, with respect to all parties to agreements or instruments relevant hereto other than the Company, that such parties had the requisite power and authority (corporate or otherwise) to execute, deliver and perform such agreements and instruments, that such agreements and instruments have been duly authorized by all requisite action (corporate or otherwise), executed and delivered by such parties and that such agreements and instruments are the valid, binding and enforceable obligations of such parties. As to questions of fact material to our opinion, we have relied upon certificates or comparable documents of officers and other representatives of the Company and of public officials.

Based on the foregoing, we are of the opinion that the Securities, when duly executed by the Company, authenticated by the Trustee in the manner provided for in the Indenture and delivered on behalf of the Company against payment of the consideration therefor specified in the Underwriting Agreement, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their terms.

Our opinion set forth above is subject to the following qualifications and exceptions:

Our opinion expressed above is limited to the laws of the States of Minnesota and New York, and the federal laws of the United States of America.

We hereby consent to the filing of this opinion as an exhibit to the Company’s Current Report on Form 8-K to be filed with the Commission on or about October 1, 2020, which Current Report on Form 8-K will be incorporated by reference into the Registration Statement, and to the reference to our firm under the caption “Legal Matters” contained in the Prospectus Supplement. In giving such consent, we do not admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission thereunder.