In a Cargo Systems Messaging Service (CSMS) bulletin published on September 22, 2026, U.S. Customs and Border Protection (CBP) provided guidance on amendments made to certain Section 301 China product exclusions.

The guidance reviews the amendments published by the Office of the U.S. Trade Representative (USTR) in the Federal Register on September 2, 2026. The USTR made conforming amendments to four product exclusions claimed under 9903.88.69 to reflect changes that occurred to the Harmonized Tariff Schedule of the United States (HTSUS) on July 1, 2026.

As a result of these amendments, some importers may have overpaid duties between July 1, 2026, and September 22, 2026, if eligible imports were not entered under the applicable 9903.88.69 exclusion during this window. CBP encourages importers to file a post summary correction (PSC) or protest, to obtain a refund of duties paid.

The Automated Commercial Environment (ACE) functionality for the conforming amendments will go into effect on September 23, 2026.

CSMS # 69990649 can be found here:
https://content.govdelivery.com/bulletins/gd/USDHSCBP-42bf8f9?wgt_ref=USDHSCBP_WIDGET_2

USTR’s Federal Register Notice on the conforming amendments can be found here:
https://www.federalregister.gov/documents/2026/09/02/2026-17925/notice-of-conforming-amendments-to-product-exclusions-chinas-acts-policies-and-practices-related-to