On September 4, 2025, President Trump, using his authority under the International Emergency Economic Powers Act (“IEEPA”), issued an executive order (“EO”) titled, Implementing The United States–Japan Agreement, to implement the trade agreement with Japan on July 22, 2025. The EO establishes a15% tariff on the majority of Japanese imports, notably including automobiles and auto parts that have previously been central to U.S.–Japan trade tensions. Under the EO, all Japanese automobiles and auto components entering the United States will face a minimum 15% tariff, unless their current tariff rate is already at or above that level, in which case no additional duties will be imposed. The EO also provides for targeted exemptions for aerospace products, certain natural resources, and generic pharmaceuticals, which will be subject to zero tariffs. These tariffs are retroactively applied to goods imported for consumption from August 7, 2025, onward.
In exchange for these measures, Japan has committed to expanding access for U.S. businesses across several sectors, pledging to purchase $8 billion of American agricultural products annually and to invest $550 billion in U.S.-designated infrastructure and manufacturing projects. The EO also grants federal agencies the authority to update tariff schedules, promulgate detailed regulations, and ensure the agreement’s robust enforcement, while overriding any conflicting executive actions previously in place.
On September 5, 2025, U.S. Customs and Border Protection (“CBP”) issued CSMS #66146676, providing guidance regarding the retroactive enforcement of the EO, which takes effect at 12:01 a.m. Eastern Daylight Time on August 7, 2025. CBP clarified that any refunds will be administered according to applicable laws and CBP’s standard refund procedures. In light of this provision, CBP has instructed the trade community not to submit Post Summary Corrections or protests until further guidance is provided on the refund submission process.
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