Exhibit 5.1

Matthew B. Hemington

+1 650 843 5062

hemingtonmb@cooley.com

June 24, 2020

1Life Healthcare, Inc.

One Embarcadero Center, Suite 1900

San Francisco, CA 94111

Ladies and Gentlemen:

We have acted as counsel to 1Life Healthcare, Inc., a Delaware corporation (the “Company”), in connection with the filing by the Company of a Registration Statement on Form S-1 (the “Registration Statement”) with the Securities and Exchange Commission pursuant to Rule 462(b) promulgated under the Securities Act of 1933, as amended, covering an underwritten public offering of up to 1,495,000 shares of the Company’s common stock, par value $0.001 per share (the “Shares”). The Registration Statement incorporates by reference the registration statement on Form S-1 (File No. 333-239347), which was declared effective on June 24, 2020 (the “Initial Registration Statement”), including the prospectus which forms a part of the Initial Registration Statement (the “Prospectus”)

In connection with this opinion, we have examined and relied upon (a) the Registration Statement, the Initial Registration Statement and the Prospectus, (b) the Company’s Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws, each as currently in effect and (c) originals or copies certified to our satisfaction of such records, documents, certificates, memoranda and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. We have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to originals of all documents submitted to us as copies, the accuracy, completeness and authenticity of certificates of public officials and the due authorization, execution and delivery of all documents by all persons other than the Company where authorization, execution and delivery are prerequisites to the effectiveness thereof. As to certain factual matters, we have relied upon a certificate of an officer of the Company and have not independently verified such matters.

Our opinion is expressed only with respect to the General Corporation Law of the State of Delaware. We express no opinion to the extent that any other laws are applicable to the subject matter hereof and express no opinion and provide no assurance as to compliance with any federal or state securities law, rule or regulation.

On the basis of the foregoing, and in reliance thereon, we are of the opinion that the Shares have been validly issued and are fully paid and non-assessable.

We consent to the reference to our firm under the caption “Legal Matters” in the Prospectus included in the Initial Registration Statement and to the filing of this opinion as an exhibit to the Registration Statement.

Cooley LLP 3175 Hanover Street Palo Alto, CA 94304-1130

t: (650) 843-5000 f: (650) 849-7400 cooley.com

1Life Healthcare, Inc.

June 24, 2020

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Cooley LLP 3175 Hanover Street Palo Alto, CA 94304-1130

t: (650) 843-5000 f: (650) 849-7400 cooley.com