Filed Pursuant to Rule 424(b)(3)

Registration No. 333-263798

PROSPECTUS SUPPLEMENT NO. 11

(To Prospectus dated June 1, 2022)

UP TO 19,354,059 SHARES OF COMMON STOCK

ISSUABLE UPON EXERCISE OF WARRANTS

UP TO 96,941,181 SHARES OF COMMON STOCK

UP TO 4,450,000 WARRANTS TO PURCHASE COMMON STOCK

This prospectus supplement supplements the prospectus, dated June 1, 2022 (the “Prospectus”), which forms a part of our registration statement on Form S-1 (No. 333-263798). This prospectus supplement is being filed to update and supplement the information in the Prospectus with the information contained in our Current Report on Form 8-K filed with the Securities and Exchange Commission on January 27, 2023 (the “Current Report”). Accordingly, we have attached the Current Report to this prospectus supplement.

The Prospectus and this prospectus supplement relate to the issuance by us of up to an aggregate of 19,354,059 shares of our common stock, $0.0001 par value per share (the “common stock”) consisting of (i) 4,450,000 shares of common stock issuable upon the exercise of 4,450,000 warrants (the “private placement warrants”) originally issued in a private placement in connection with the initial public offering (the “IPO”) of Supernova Partners Acquisition Company II, Ltd., a Cayman Islands exempted company (“Supernova”), by the holders thereof, (ii) 8,624,972 shares of common stock issuable upon the exercise of 8,624,972 warrants (the “public warrants” and, together with the private placement warrants, the “warrants”) originally issued in the IPO by holders thereof, and (iii) 6,279,087 shares of common stock issuable upon the exercise of warrants assumed by us and converted into warrants to purchase common stock (the “Rigetti assumed warrants”) in connection with the Business Combination (as defined below). We will receive the proceeds from the exercise of any warrants and any Rigetti assumed warrants for cash.

The Prospectus and this prospectus supplement also relate to the offer and sale from time to time by the selling securityholders named in this prospectus or their permitted transferees (the “selling securityholders”) of up to (i) 96,941,181 shares of common stock consisting of (a) 10,251,000 shares of common stock purchased by subscribers at a price of $10.00 per share and 4,390,244 shares of common stock purchased by subscribers at a price of $10.25 per share in private placements pursuant to separate subscription agreements, (b) 8,625,000 shares of common stock (the “Founder Shares”) originally purchased by Supernova Partners II LLC (“Supernova Sponsor”) for $25,000, or for approximately $0.004 per share, in a private placement in connection with the IPO, including 3,059,273 Founder Shares subject to vesting and forfeiture (the “Sponsor Vesting Shares”), (c) 4,450,000 shares of common stock issuable upon exercise of the private placement warrants, (d) 2,446,716 shares of common stock issuable pursuant to the exercise of Rigetti assumed warrants, which Rigetti assumed warrants have a weighted average exercise price of $0.6628 per share, (e) 6,226,065 shares of common stock issuable upon exercise of outstanding options, which have an exercise price of $0.272 per share, (f) 6,288,369 shares of common stock issuable in connection with the vesting and settlement of outstanding restricted stock units, which were assumed by and converted into restricted stock awards for common stock in connection with the Business Combination based on an acquiror share value of $10.00 per share and (g) 54,263,787 shares of common stock issued in connection with the Business Combination as merger consideration at an acquiror share value of $10.00 per share, and (ii) up to 4,450,000 private placement warrants, which were purchased by Supernova Sponsor at a price of $2.00 per warrant. We will not receive any proceeds from the sale of shares of common stock or warrants by the selling securityholders pursuant to this prospectus.

This prospectus supplement updates and supplements the information in the Prospectus and is not complete without, and may not be delivered or utilized except in combination with, the Prospectus, including any amendments or supplements thereto. This prospectus supplement is qualified by reference to the Prospectus, including any amendments or supplements thereto, except to the extent that the information in this prospectus supplement updates and supersedes the information contained therein.

Our common stock and public warrants are listed on the Nasdaq Capital Market under the symbols “RGTI” and “RGTIW,” respectively. On January 26, 2023, the last reported sales price of our common stock was $0.808 per share and the last reported sales price of our public warrants was $0.089 per warrant.

We are an “emerging growth company” as defined under U.S. federal securities laws and, as such, have elected to comply with reduced public company reporting requirements. The Prospectus complies with the requirements that apply to an issuer that is an emerging growth company.

Investing in our securities involves a high degree of risks. You should review carefully the risks and uncertainties described in the section titled “Risk Factors” beginning on page 16 of the Prospectus, and under similar headings in any amendments or supplements to the Prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the accuracy or adequacy of the Prospectus or this prospectus supplement. Any representation to the contrary is a criminal offense.

Prospectus Supplement dated January 27, 2023.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): January 25, 2023

RIGETTI COMPUTING, INC.

(Exact name of registrant as specified in its charter)

(510) 210-5550

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligations of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

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.  ☐

On January 25, 2023, Rigetti Computing, Inc. (the “Company”) received a letter from the Listing Qualifications Department of The Nasdaq Stock Market, LLC, (“Nasdaq”), indicating that, based on the closing bid price for the previous 30 consecutive business days, the listing of the Company’s common stock was not in compliance with Nasdaq Listing Rule 5550(a)(2) to maintain a minimum bid price of $1.00 per share (the “Bid Price Rule”).

Nasdaq Listing Rule 5810(c)(3)(A) provides a compliance period of 180 calendar days, or until July 24, 2023 (the “Compliance Date”), to regain compliance. If at any time during this 180-day period the closing bid price of the Company’s common stock is at least $1.00 for a minimum of ten consecutive business days, the Company will regain compliance. If the Company is unable to regain compliance before the Compliance Date, the Company may be eligible for an additional 180 calendar days to satisfy the Bid Price Rule. To qualify, the Company will be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for the Nasdaq Capital Market with the exception of the Bid Price Rule, and will need to provide written notice of its intention to cure the deficiency during such additional compliance period, by effecting a reverse stock split, if necessary. However, if it appears to Nasdaq staff that the Company will not be able to cure the deficiency, or if the Company is otherwise not eligible for the additional compliance period, and the Company does not regain compliance by the Compliance Date, the Nasdaq Capital Market will provide written notification to the Company that its common stock is subject to delisting. At that time, the Company may appeal the delisting determination to a hearings panel pursuant to the procedures set forth in the applicable Nasdaq Listing Rules. However, there can be no assurance that, if the Company does appeal the delisting determination by Nasdaq to the panel, such appeal would be successful.

The Company intends to actively monitor the closing bid price of its common stock and, as appropriate, will consider available options to regain compliance with the Bid Price Rule, including potentially seeking to effect a reverse stock split. There can be no assurance that the Company will be able to regain compliance with Nasdaq’s Listing Rule 5550(a)(2) or will otherwise be in compliance with other Nasdaq listing criteria and that the Company will be able to maintain its listing with Nasdaq.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: January 27, 2023