By Helen Reid

March 3 (Reuters) - On Holding ONON.N sees lower U.S. tariff rates after the Supreme Court struck down the government's emergency levies as a possible boost for the fast-growing Swiss sportswear brand, CEO Martin Hoffmann said on Tuesday as it delivered strong quarterly results.

The company, which sells running shoes for $150 and up, forecast at least 23% sales growth in 2026 on a constant-currency basis — moderating from the 30% growth reported in 2025, yet outpacing bigger rivals Nike NKE.N and Adidas ADSGn.DE.

On also sees annual profit margin increasing to at least 63% from 62.8% in 2025, with the outlook not yet factoring in a lower U.S. tariff rate.

The U.S., On's biggest market, began collecting a temporary new 10% blanket tariff on imports last week, with plans to lift it to 15%. Even then, it would remain well below the additional 20% duty imposed last year on countries such as Vietnam and Indonesia, key sourcing hubs for On.

"If we see 15% becoming the new reality, this would be an additional upside to the guidance that we gave," Hoffmann told Reuters.

On's fourth-quarter sales rose 22.6% to 743.8 million Swiss francs ($949.69 million), helped by limited discounting during the holiday season. Analysts' on average estimated 724.3 million francs, according to data compiled by LSEG.

A focus on affluent shoppers has helped the company, while brands targeting lower-income consumers have been burned as they cut spending in an increasingly polarized economy, especially in the U.S.

"The strong product pipeline that we have, the innovation that we bring to the market, and that premium position is really building momentum globally, and is resonating with the customer globally," Hoffmann said, adding that the brand plans 10 to 15 store openings this year.

Quarterly adjusted earnings before interest, taxes, depreciation and amortization rose 31.8% to 131 million francs.

Hoffmann also said On was among the companies that have filed for tariff refunds and that any proceeds would be reinvested in the business rather than passed on to consumers.

($1 = 0.7832 Swiss francs)

(Reporting by Neil J Kanatt in Bengaluru and Helen Reid in Paris; Editing by Shilpi Majumdar)

((Neil.JKanatt@thomsonreuters.com))