Filed pursuant to Rule 424(b)(3)
Registration No. 333-285279
SUPPLEMENT NO 1. DATED March 11, 2025
TO
PROSPECTUS SUPPLEMENT DATED February 26, 2025
(To Prospectus Dated February 26, 2025)
IonQ, Inc.
This Supplement No. 1 to Prospectus Supplement (this Supplement) supplements and amends the Prospectus Supplement dated
February 26, 2025 (the Prospectus Supplement). This Supplement should be read in conjunction with the Prospectus Supplement and the accompanying Prospectus dated February 26, 2025 (the Prospectus). This Supplement
is qualified by reference to the Prospectus Supplement, except to the extent that the information presented herein supersedes the information contained in the Prospectus Supplement.
On February 26, 2025, we entered into an Equity Distribution Agreement (the Equity Distribution Agreement) with Morgan
Stanley & Co. LLC and Needham & Company, LLC as sales agents (the Sales Agents) relating to shares of our common stock offered by the Prospectus Supplement and the accompanying Prospectus. In accordance with the terms
of the Equity Distribution Agreement, we had the opportunity to offer and sell shares of our common stock having an aggregate offering price of up to $500,000,000 from time to time through the Sales Agents pursuant to
at-the-market transactions (the ATM). As of the date of this Supplement, we have sold an aggregate of 16,038,460 shares of our common stock pursuant to the
Equity Distribution Agreement for aggregate gross proceeds of approximately $372.6 million.
The purpose of this Supplement is to
terminate the ATM and to terminate the continuous offering by us under the Prospectus Supplement, effective on March 11, 2025. The Equity Distribution Agreement was terminated on March 10, 2025.
Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the
adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.
The date of
this Supplement No. 1 to Prospectus Supplement is March 11, 2025.