As filed with the Securities and Exchange Commission on February 6, 2026

Registration No. 333-   

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Biodesix, Inc.

(Exact name of Registrant as Specified in Its Charter)

Biodesix, Inc. 2020 Equity Incentive Plan

Biodesix, Inc. Employee Stock Purchase Plan

(Full Title of the Plan)

Scott Hutton

President and Chief Executive Officer

Biodesix, Inc.

919 W. Dillon Road

Louisville, Colorado 80027

(303) 417-0500

(Name, Address and Telephone Number, Including Area Code, of Agent for Service)

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.

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 7(a)(2)(B) of the Securities Act. ☐

EXPLANATORY NOTE

This Registration Statement on Form S-8 is being filed by Biodesix, Inc. (the “Registrant”) for the purpose of registering (i) an additional 330,122 shares of the Registrant’s common stock, par value $0.001 per share (the “Common Stock”) issuable under the Biodesix, Inc. 2020 Equity Incentive Plan (the “2020 Plan”), as a result of the operation of the automatic annual increase provision therein effective January 1, 2026, and (ii) an additional 82,531 shares of Common Stock issuable under the Biodesix, Inc. Employee Stock Purchase Plan, as amended and restated (the “ESPP”), as a result of the operation of the automatic annual increase provision therein effective January 1, 2026. The shares of the Registrant’s Common Stock previously reserved for issuance under the 2020 Plan were registered on the Registrant’s Registration Statement on Form S-8 filed with the Securities and Exchange Commission (the “Commission”) on November 2, 2020 (File No. 333-249805) (the “2020 Prior Form S-8”), the Registrant’s Registration Statement on Form S-8 filed with the Commission on June 6, 2022 (File No. 333-265445) (the “2022 Prior Form S-8”), the Registrant’s Registration Statement on Form S-8 filed with the Commission on February 2, 2023 (File No. 333-269536) (the “2023 Prior Form S-8”), the Registrant’s Registration Statement on Form S-8 filed with the Commission on February 2, 2024 (File No. 333-276842) (the “2024 Prior Form S-8”), and the Registrant’s Registration Statement on Form S-8 filed with the Commission on February 7, 2025 (File No. 333-284767) (the “2025 February Prior Form S-8”). The shares of the Registrant’s Common Stock previously reserved for issuance under the ESPP were registered on the 2020 Prior Form S-8, the 2023 Prior Form S-8, the 2024 Prior Form S-8, the 2025 February Prior Form S-8, and the Registrant’s Registration Statement on Form S-8 filed with the Commission on May 30, 2025 (File No. 333-287678) (the “2025 May Prior Form S-8”, together with the 2020 Prior Form S-8, the 2022 Prior Form S-8, the 2023 Prior Form S-8, the 2024 Prior Form S-8, and the 2025 February Prior Form S-8, the “Prior Forms S-8”).

This Registration Statement on Form S-8 relates to securities of the same class as that to which the Prior Forms S-8 relate, and is submitted in accordance with General Instruction E to Form S-8 regarding Registration of Additional Securities. Pursuant to General Instruction E of Form S-8, the contents of the Prior Forms S-8, to the extent relating to the registration of Common Stock issuable under the 2020 Plan and the ESPP, are incorporated herein by reference and made part of this Registration Statement on Form S-8, except as amended hereby. The shares of Common Stock registered by the Prior Forms S-8 have been automatically adjusted to give effect to the Registrant’s 1-for-20 reverse stock split of the issued and outstanding shares of Common Stock effective on September 15, 2025.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

The Registrant hereby incorporates by reference in this Registration Statement the following documents and information previously filed with the Commission (excluding any portions of such documents that have been “furnished” but not “filed” for purposes of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)):

All documents subsequently filed by the Registrant with the Commission pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference into this Registration Statement and to be a part hereof from the respective dates of filing of such documents (such documents, and the documents enumerated above, being hereinafter referred to as “Incorporated Documents”).

Any statement contained in an Incorporated Document shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed Incorporated Document modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended (the “Securities Act”), the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Louisville, Colorado, on the 6th day of February, 2026.

POWER OF ATTORNEY AND SIGNATURES

Each of the undersigned officers and directors of Biodesix, Inc. does hereby severally constitute and appoint Scott Hutton and Robin Harper Cowie, and each of them acting alone, his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them for him or her and in his or her name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission and any applicable securities exchange or securities self-regulatory body, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Exhibit 5.1

February 6, 2026

Biodesix, Inc.

919 W. Dillon Road

Louisville, CO 80027

Ladies and Gentlemen:

We refer to the Registration Statement on Form S-8 (the “Registration Statement”) being filed by Biodesix, Inc., a Delaware corporation (the “Company”), with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”), relating to the registration of (i) 330,122 shares of Common Stock, $0.001 par value per share (the “Common Stock”), of the Company which may be issued under the Biodesix, Inc. 2020 Equity Incentive Plan (the “2020 Plan”) and (ii) 82,531 shares of Common Stock which may be issued under the Biodesix, Inc. Employee Stock Purchase Plan (the “ESPP”, and together with the aggregate shares of Common Stock to be registered under the Registration Statement, the “Registered Shares”).

This opinion letter is being delivered in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

We have examined the 2020 Plan, the ESPP, the Registration Statement, the Amended and Restated Certificate of Incorporation of the Company, the Amended and Restated Bylaws of the Company, the resolutions of the Company’s Board of Directors authorizing the 2020 Plan, the ESPP and the issuance of the Registered Shares thereunder and the resolutions of the Company’s stockholders authorizing the 2020 Plan and the ESPP. We have also examined originals, or copies of originals certified to our satisfaction, of such agreements, documents, certificates and statements of the Company and other corporate documents and instruments, and have examined such questions of law, as we have considered relevant and necessary as a basis for this opinion letter. We have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures, the legal capacity of all persons and the conformity with the original documents of any copies thereof submitted to us for examination. As to facts relevant to the opinions expressed herein, we have relied without independent investigation or verification upon, and assumed the accuracy and completeness of, certificates, letters and oral and written statements and representations of public officials and officers and other representatives of the Company.

Biodesix, Inc.

February 6, 2026

Page 2

Based on the foregoing, we are of the opinion that each Registered Share that is newly issued pursuant to the 2020 Plan and the ESPP will be validly issued, fully paid and non-assessable when: (i) the Registration Statement, as finally amended, shall have become effective under the Securities Act; (ii) such Registered Share shall have been duly issued and delivered in accordance with the 2020 Plan and the ESPP; and (iii) certificates representing such Registered Share shall have been duly executed, countersigned and registered and duly delivered to the person entitled thereto against payment of the agreed consideration therefor (in an amount not less than the par value thereof) or, if any Registered Share is to be issued in uncertificated form, the Company’s books shall reflect the issuance of such Registered Share to the person entitled thereto against payment of the agreed consideration therefor (in an amount not less than the par value thereof), all in accordance with the 2020 Plan and the ESPP.

This opinion letter is limited to the General Corporation Law of the State of Delaware. We express no opinion as to the laws, rules or regulations of any other jurisdiction, including, without limitation, the federal laws of the United States of America or any state securities or blue sky laws.

We hereby consent to the filing of this opinion letter as an Exhibit to the Registration Statement and to all references to our Firm included in or made a part of the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the use of our report dated March 3, 2025, with respect to the financial statements of Biodesix, Inc., incorporated herein by reference.

/s/ KPMG LLP

Denver, Colorado

February 6, 2026