Overview
- An International Trade Administration notice put the new 15% rate into effect Tuesday, following the Sept. 4 executive order that operationalized the U.S.–Japan agreement.
- The cut reduces the effective duty from 27.5% to 15% for Japanese automobiles and key parts such as engines and transmissions.
- The guidance formalizes a no-stacking policy and provides retroactive refunds for excess duties collected since Aug. 7.
- South Korean vehicles remain subject to a 25% sectoral levy as follow-up talks on a similar 15% cap continue with no clear start date.
- Japan’s exports to the United States fell 13.8% in August, led by a steep drop in auto shipments, and industry groups say the 15% rate still weighs on margins compared with pre-2025 levels.