6-K

UNITED STATES

SECURITIES AND EXCHANGECOMMISSION

WASHINGTON, DC 20549

FORM 6-K

REPORTOF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGEACT OF 1934

For the month of September2025

Commission File Number: 001-41782

VinFast Auto Ltd.

Dinh Vu – CatHai Economic Zone

Cat Hai Island, CatHai Special Zone

Hai Phong City, Vietnam

(Address of principalexecutive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.    Form 20-F  ☒   Form 40-F  ☐

INFORMATIONCONTAINED IN THIS REPORT ON FORM 6-K

VINFASTDELIVERED 10,922 ELECTRIC VEHICLES IN VIETNAM IN AUGUST 2025

Hanoi, September 12,2025 – VinFast Auto Ltd. (the “Company” or “VinFast”) announced its preliminary domestic Vietnam deliveriesof 10,922 electric vehicles (“EVs”)^1^ in August 2025. In total, the Company has delivered 89,970^1^ EVsto customers in Vietnam during the first eight months of 2025.

With this result, VinFast’s monthly deliveries in Vietnam have remained relatively steady at approximately 11,000 EVs for several consecutive months, enabling the Company to maintain its position as the leading car manufacturer in terms of vehicle deliveries in Vietnam^2^. Notably, 2,745 VF 5 vehicles^1^ were delivered in August 2025, making it VinFast’s best-selling model for the month. The VF 3 followed closely with 2,481 vehicles^1^ delivered. The Herio Green ranked third with 2,395 vehicles^1^ delivered, followed by the VF 6 with 2,038 vehicles^1^ and the VF 7 with 718 vehicles^1^.

From the beginning of the year through August 2025, the VF 3 and VF 5 were the two best-selling models in Vietnam with cumulative deliveries of 28,704 and 27,109 vehicles^1^, respectively. The Company also delivered 12,492 VF 6 vehicles^1^ and 5,099 VF 7 vehicles^1^ during the period.

This Form 6-K shall be deemed to be incorporated by reference into the Company’s registration statement on Form S-8 (File No. 333-278251) and registration statement on Form F-3 (File No. 333-275133) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is furnished, to the extent not superseded by documents or reports subsequently filed or furnished.

Note 1: Preliminary delivery results are subjectto change and may differ from the final number of deliveries that will be recognized as vehicle sales revenue for the period as a resultof the year end audit.

Note 2: Market and industry statements in thisdocument are based on data from the Vietnam Automobile Manufacturers' Association and Company internal data (for VinFast only).

About VinFast

VinFast (NASDAQ: VFS) – a subsidiaryof Vingroup JSC – is Vietnam’s leading automotive manufacturer, committed to its mission of creating a green future for everyone.VinFast produces a range of electric SUVs, e-scooters, e-bikes, and e-buses in Vietnam and exports to key markets across Asia, North America,and Europe. Learn more at www.vinfastauto.us.

VinFast deliveries represent only one measureof the Company’s financial performance and should not be relied on as an indicator of quarterly financial results, which dependon a variety of factors, including the average selling price and various cost components.

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SIGNATURE

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

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