U.S. Supreme Court Ruling on IEEPA Tariffs and new Presidential Proclamation – Key Takeaways and Implications

As of today 6:00 a.m. Swiss time (CET) on February 24, 2026 (12:01 a.m. Eastern Standard Time), an additional 10% ad valorem duty applies to imported articles from all countries for a period of 150 days, unless specifically exempt.

This measure applies to articles that are the product of any country and that are entered for consumption, or withdrawn from warehouse for consumption, on or after 12:01 a.m. Eastern Standard Time on February 24, 2026, and through 12:01 a.m. Eastern Daylight Time on July 24, 2026, as per the relevant guidance provided by U.S. Customs and Border Protection (CBP).

What about the 15%

Please note that, as of the time of writing, there has been no Presidential Action published with regard to an increase of the Section 122 temporary surcharge from 10% to 15%, as previously referenced by the President in a Truth Social post. Some media report that the White House is working on a formal order that will increase the global tariff rate to 15%.

How are the 10% additional tariffs calculated

In contrast to the 15% “all-in” tariff cap (i.e. unstacked) agreed upon in the Swiss–U.S. Joint Statement of November 14, 2025, the 10% duty imposed under Section 122 is applied on top of the most-favored-nation (MFN) tariff rate in force prior to April 2, 2025 (i.e. stacked). MFN tariff rates are product-specific.

For the sake of clarity, and in response to several member requests, I have prepared the illustrative table below:

Total combined tariff rate (illustrative examples)

 
  Until April 2, 2025 Aug 1, 2025  – Nov 14, 2025 (+39% stacked) Nov 14, 2025 – Feb 21, 2026 (15% all-in cap; MFN applies if higher) Feb 21, 2026 – July 24, 2026 (+10% stacked)
 Product A 3% 42% 15% 13%
 Product B 8% 47% 15% 18%
 Product C 19% 58% 19% 29%

What about the Swiss–U.S. Joint Statement of November 14, 2025

As of the time of writing, it remains unclear whether the Swiss–U.S. Joint Statement of November 14, 2025 qualifies as a trade deal and whether, and in what manner, it could supersede the Section 122 tariffs or take effect upon expiration of the 150-day period. At present, the Joint Statement is expressly non-binding in nature and reflects the intention of both parties to negotiate a future agreement.

We will keep you informed as further guidance and clarification become available.