NoteU.S. Customs and Border Protection · Tariffs & customsEffective Oct 23, In force4/4 quoted sentences found in the source

A fifth Section 301 China exclusion is matched to the July 1 tariff numbers; duty paid since then can be claimed back by correction

CBP updated its September guidance after USTR amended one more Section 301 China exclusion to match tariff numbers that changed on July 1, 2026. The added exclusion covers goods now reported under statistical number 8479.90.9591. CBP's system accepts the amended exclusions from 6 pm on October 23, 2026, and importers who paid the duty on qualifying entries can file a Post Summary Correction, or a protest if the correction window has passed.

Accepted from6 pm on October 23, 2026
Statistical number8479.90.9591
Exclusion heading9903.88.69

What the document says

Matched to source. CBP's system accepts the amendment from 6 pm on October 23, 2026.
Matched to source. The added exclusion now points to statistical number 8479.90.9591.
Matched to source. Duty already paid can be recovered by a Post Summary Correction.
Matched to source. If the correction window has closed, a protest is the route.

Who does this affect?: Importers of Chinese machinery parts under 8479.90.9591, and of the pump parts and plastic articles covered by the four exclusions amended in September.
What it costs: The Section 301 China duty paid since July 1, 2026 on goods that qualify for the amended exclusion, recoverable by Post Summary Correction.
What to check: If you import Chinese goods under 8479.90.9591, ask your broker whether entries since July 1 carried exclusion heading 9903.88.69 and, if not, whether a Post Summary Correction can still be filed.

The headline, summary, who, cost, and what-to-check lines are our reading of the document, not the document’s words and not advice.

Primary source

CSMS #70261629: UPDATED GUIDANCE: Section 301 China Conforming Amendment