Stardust Power Inc美股招股说明书(2026-03-30版)

STARDUST POWER INC. Up to 2,000,000 Shares of Common Stock This prospectus supplement supplements the prospectus dated February 17, 2026 (the “Prospectus”), which forms a part of our registration statement on FormS-1 (No. 333-293405). This prospectus supplement is being filed to update and supplement the information in the Prospectus with the information contained in ourForm 10-K filed with the Securities and Exchange Commission (the “SEC”) on March 25, 2026 (the “Form 10-K”). Accordingly, we have attached the Form 10-K tothis prospectus supplement. The Prospectus relates to the offer and resale of up to 2,000,000 shares of our common stock, $0.0001 per share (the “Common Stock”), by B. Riley PrincipalCapital II, LLC (the “Selling Stockholder”). The shares included in this Prospectus consist of shares of Common Stock that we have issued or that we may, in ourdiscretion, elect to issue and sell to the Selling Stockholder, from time to time after the date of this Prospectus, pursuant to a Common Stock Purchase Agreement weentered into with the Selling Stockholder on February 12, 2026 (the “Purchase Agreement”), in which the Selling Stockholder has committed to purchase from us, atour direction, up to $10,000,000 of our Common Stock, subject to terms and conditions specified in the Purchase Agreement. Our Common Stock is listed on The Nasdaq Capital Market under the symbols “SDST”. On March 26, 2026, the last reported sales price of our CommonStock was $2.32 per share. We are an “emerging growth company” and a “smaller reporting company” as defined under U.S. federal securities laws and, as such, have elected to complywith reduced public company reporting requirements. The Prospectus and this prospectus supplement comply with the requirements that apply to an issuer that is anemerging growth company and a smaller reporting company. This prospectus supplement updates and supplements the information in the Prospectus and is notcomplete without, and may not be delivered or utilized except in combination with, the Prospectus, including any amendments or supplements thereto. This prospectussupplement should be read in conjunction with the Prospectus and if there is any inconsistency between the information in the Prospectus and this prospectussupplement, you should rely on the information in this prospectus supplement. Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described in the section titled “RiskFactors” beginning on page 15 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 uponthe accuracy or adequacy of the Prospectus or this prospectus supplement. Any representation to the contrary is a criminal offense. The date of this prospectus supplement is March 27, 2026. UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549 FORM 10-K ☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2025 ☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number: 001-39875 STARDUST POWER INC.(Exact name of registrant as specified in its charter) Registrant’s telephone number, including area code:(800) 742-3095 Not applicable(Former name or former address, if changed since last report) Securities registered pursuant to Section 12(b) of the Act: Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☐No☒ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes☐No☒ Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during thepreceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90days. Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Date File required to be submitted pursuant to Rule 405 of Regulation S-T(§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒No☐ 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 emerginggrowth company. See definitions of “large accelerated filer”, “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of theExchange Act. ☐Accelerated filer☒Smaller reporting companyEmerging growth company Large accelerated filerNon-accelerated filer If an emergi