6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of October 2025

Commission File Number: 001-41431

Polestar Automotive Holding UK PLC

Assar Gabrielssons Väg 9

405 31 Göteborg, Sweden

(Address of principal executive 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  x                Form 40-F  ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ¨

INFORMATION CONTAINED IN THIS REPORT ON FORM 6-K

On October 9, 2025, Polestar Automotive Holding UK PLC (“Polestar”) issued a press release announcing its preliminary estimates for global volumes for the third quarter of 2025. A copy of the press release is attached hereto as Exhibit 99.1.

Exhibit 99.1 to this Report on Form 6-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

EXHIBIT INDEX

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, thereunto duly authorized.

Exhibit 99.1

Polestar reports 36% retail sales growth for the first nine monthsof 2025

GOTHENBURG, SWEDEN – 9 October 2025 – Polestar (Nasdaq: PSNY) retail sales amounted to an estimated 14,192 cars in Q3 2025, up 13% versus Q3 2024. For the first nine months of the year, retail sales approximated 44,482 cars, a growth of 36% compared to the same period last year.

Michael Lohscheller, Polestar CEO, says: “The third quarter saw continued growth, and we have now sold as many cars as in the whole of 2024. Despite continued external headwinds and challenging market conditions, our line-up and strong order intake provide a solid basis for growth in the fourth quarter.”

Breakdown of retail sales volumes:

Polestar expects to publish select results for the third quarter 2025 and hold an analyst conference call on 12 November 2025.

Ends.

Contacts

Anna Gavrilova

Head of Investor Relations

[email protected]

Theo Kjellberg

Head of Corporate Communication

[email protected]

About Polestar

Polestar (Nasdaq: PSNY) is the Swedish electric performance car brand with a focus on uncompromised design and innovation, and the ambitionto accelerate the change towards a sustainable future. Headquartered in Gothenburg, Sweden, its cars are available in 28 markets globallyacross North America, Europe and Asia Pacific.

Polestar has four models in its line-up: Polestar 2, Polestar 3,Polestar 4, and Polestar 5. Planned models include the Polestar 6 roadster and the Polestar 7 compact SUV. With its vehicles currentlymanufactured on two continents, North America and Asia, Polestar plans to diversify its manufacturing footprint further, with productionof Polestar 7 planned in Europe.

Polestar has an unwavering commitment to sustainability and hasset an ambitious roadmap to reach its climate targets: halve greenhouse gas emissions by 2030 per-vehicle-sold and become climate-neutralacross its value chain by 2040. Polestar’s comprehensive sustainability strategy covers the four areas of Climate, Transparency,Circularity, and Inclusion.

Forward-Looking Statements

Certain statements in this press release (“Press Release”)may be considered “forward-looking statements” as defined in the Private Securities Litigation Reform Act of 1995. Forward-lookingstatements generally relate to future events or the future financial or operating performance of Polestar including the number of vehicledeliveries and gross margin. For example, projections of revenue, volumes, margins, cash flow break-even and other financial or operatingmetrics and statements regarding expectations of future needs for funding and plans related thereto are forward-looking statements. Insome cases, you can identify forward-looking statements by terminology such as “may”, “should”, “expect”, “intend”, “will”, “estimate”, “anticipate”, “believe”, “predict”, “potential”, “forecast”, “plan”, “seek”, “future”, “propose”or “continue”, or the negatives of these terms or variations of them or similar terminology. Such forward-looking statementsare subject to risks, uncertainties, and other factors which could cause actual results to differ materially from those expressed orimplied by such forward looking statements.

These forward-looking statements are based upon estimates and assumptionsthat, while considered reasonable by Polestar and its management, as the case may be, are inherently uncertain. Factors that may causeactual results to differ materially from current expectations include, but are not limited to: (1) Polestar’s ability to enterinto or maintain agreements or partnerships with its strategic partners, including Volvo Cars and Geely, original equipment manufacturers,vendors and technology providers; (2) Polestar’s ability to maintain relationships with its existing suppliers, source newsuppliers for its critical components and enter into longer term supply contracts and complete building out its supply chain; (3) Polestar’sability to raise additional funding; (4) Polestar’s ability to successfully execute cost-cutting activities and strategicefficiency initiatives; (5) Polestar’s estimates of expenses, profitability, gross margin, cash flow, and cash reserves; (6) theidentification and remediation of accounting errors and/or a final assessment of errors already identified that differs significantlyfrom Polestar’s preliminary view of such errors and the successful filing of restatements of any SEC reports; (7) Polestar’sability to continue to meet stock exchange listing standards; (8) changes in domestic and foreign business, market, financial, politicaland legal conditions; (9) demand for Polestar’s vehicles or car sale volumes, revenue and margin development based on pricing,variant and market mix, cost reduction efficiencies, logistics and growing aftersales; (10) delays in the expected timelines forthe development, design, manufacture, launch and financing of Polestar’s vehicles and Polestar’s reliance on a limited numberof vehicle models to generate revenues; (11) increases in costs, disruption of supply or shortage of materials, in particular for lithium-ioncells or semiconductors; (12) risks related to product recalls, regulatory fines and/or an unexpectedly high volume of warranty claims;(13) Polestar’s reliance on its partners to manufacture vehicles at a high volume, some of which have limited experience in producingelectric vehicles, and on the allocation of sufficient production capacity to Polestar by its partners in order for Polestar to be ableto increase its vehicle production volumes; (14) the ability of Polestar to grow and manage growth profitably, maintain relationshipswith customers and suppliers and retain its management and key employees; (15) risks related to future market adoption of Polestar’sofferings; (16) risks related to Polestar’s current distribution model and the evolution of its distribution model in the future;(17) the effects of competition and the high barriers to entry in the automotive industry and the pace and depth of electric vehicleadoption generally on Polestar’s future business; (18) changes in regulatory requirements (including environmental laws and regulationsand regulations related to connected vehicles), governmental incentives, tariffs and fuel and energy prices; (19) Polestar’s relianceon the development of vehicle charging networks to provide charging solutions for its vehicles and its strategic partners for servicingits vehicles and their integrated software; (20) Polestar’s ability to establish its brand and capture additional market share,and the risks associated with negative press or reputational harm, including from electric vehicle fires; (21) the outcome of any potentiallitigation, including litigation involving Polestar and Gores Guggenheim, Inc., government and regulatory proceedings, tax audits,investigations and inquiries; (22) Polestar’s ability to continuously and rapidly innovate, develop and market new products; (23)the impact of the ongoing conflict between Ukraine and Russia and in Israel, the Gaza Strip and the Red Sea; and (24) other risks anduncertainties set forth in the sections entitled “Risk Factors” and “Cautionary Note Regarding Forward-Looking Statements”in Polestar’s Form 20-F, and other documents filed, or to be filed, with the SEC by Polestar. There may be additional risksthat Polestar presently does not know or that Polestar currently believes are immaterial that could also cause actual results to differfrom those contained in the forward-looking statements.

Nothing in this Press Release should be regarded as a representationby any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-lookingstatements will be achieved. You should not place undue reliance on forward-looking statements, which speak only as of the date theyare made. Polestar assumes no obligation to update these forward-looking statements, even if new information becomes available in thefuture, except as may be required by law.