Section 301 Refund Playbook for the September 23 ACE Window

A narrow systems change has created a significant Section 301 refund opportunity for importers of certain Chinese-origin products. Brokers and compliance teams should now identify affected July–September 2026 entries, validate exclusion eligibility, and pursue recovery through Post Summary Corrections or protests before the applicable deadlines close.

Why the Conforming Amendment Matters

The underlying issue began when certain ten-digit HTSUS statistical reporting numbers changed effective July 1, 2026. Four existing product exclusions under 9903.88.69 still described eligible merchandise, but their tariff references had not yet been aligned with the new statistical numbers. The conforming amendment corrected that mismatch without expanding the substantive scope of the exclusions.

Old and New Statistical Reporting Numbers

Three exclusions in U.S. notes 20(vvv)(i)(4), 20(vvv)(i)(5), and 20(vvv)(i)(6) previously covered goods reported through June 30, 2026 under:

• 8413.91.9065
• 8413.91.9085
• 8413.91.9096

Effective July 1, 2026, the corresponding exclusions reference:

• 8413.91.9039
• 8413.91.9046
• 8413.91.9059
• 8413.91.9099

The exclusion in note 20(vvv)(iv)(4) previously referenced 3926.90.9910 for goods entered through June 30, 2026. Effective July 1, it references 3926.90.9915 or 3926.90.9920.

This Is Not a New Product Exclusion

The amendment generally preserves the existing exclusion coverage following statistical renumbering. It does not create a new exclusion, broaden product descriptions, or make otherwise ineligible merchandise eligible merely because it falls under one of the new ten-digit numbers.

Eligibility must still be evaluated against the applicable product description, country of origin, entry date, and Chapter 99 requirements. The exclusions also were not extended by the conforming amendment and remain scheduled to expire at 11:59 p.m. EDT on November 9, 2026. Importers should therefore separate two questions: whether merchandise fits the exclusion and whether an overpayment arose because ACE could not initially process the revised statistical number.

Identifying Entries Eligible for a Section 301 Refund

ACE began accepting the conforming amendment at noon ET on September 23, 2026. That systems deployment is operationally important because the tariff changes applied to qualifying entries effective July 1, creating a period during which some importers paid Section 301 duties that should not have been assessed.

Build the Review Population

The primary review population generally consists of Chinese-origin goods entered from July 1 through September 22, 2026 that meet all of the following conditions:

1. The merchandise was classified under one of the revised statistical reporting numbers.
2. The merchandise satisfied an applicable exclusion description under 9903.88.69.
3. Section 301 duties were paid because the exclusion claim could not be accepted under the revised tariff structure.
4. The entry remains eligible for correction through a PSC or, if liquidated, through a timely protest.

Entries transmitted around the September 23 deployment should also be checked individually. Filings submitted before ACE functionality became available may have generated rejections, required workarounds, or resulted in duty payment.

Validate More Than the Tariff Number

A matching ten-digit HTSUS number is only a screening criterion. The compliance file should establish that the imported product falls within the precise exclusion language. Useful supporting records typically include specifications, technical drawings, purchase orders, part-level classification records, country-of-origin support, entry summaries, and duty calculation worksheets.

When 9903.88.69 is properly claimed, the corresponding Chapter 99 number imposing the Section 301 China duties should not also be submitted. The ordinary Chapter 1–97 classification remains necessary, along with any other Chapter 99 reporting that independently applies.

Importers should reconcile broker data against accounts payable and landed-cost records. Section 301 duties may appear in entry data, broker statements, accrual accounts, or product costing systems, and discrepancies between these sources can conceal recoverable amounts.

Filing PSCs and Protests Without Creating New Compliance Risk

For eligible unliquidated entries within the permitted correction period, a Post Summary Correction is generally the most direct recovery mechanism. If the PSC pathway is no longer available, the importer may need to protest liquidation within the applicable protest timeframe.

PSC Workflow for the September 23 Window

A controlled PSC process should include the following steps:

• Extract entries from July 1 through September 22 using importer, origin, HTSUS, entry date, and Chapter 99 fields.
• Confirm that each product satisfies the applicable exclusion description rather than relying solely on tariff classification.
• Recalculate duties using 9903.88.69 and remove the corresponding Section 301 duty assessment.
• Verify liquidation status and the remaining PSC filing period before transmission.
• Submit PSCs on or after September 23, 2026, and monitor ACE for acceptance or rejection.
• Retain the eligibility analysis, revised duty calculation, system response, and refund reconciliation.

PSC batches should be prioritized by deadline, duty value, and documentation readiness. High-value entries approaching liquidation generally warrant immediate attention, while lower-value entries can be processed through a controlled batch workflow.

Protest and Drawback Considerations

Once an entry is outside the PSC filing window, the importer should determine whether liquidation may be protested. Protest rights are deadline-sensitive, and a request for internal review or a broker inquiry does not generally preserve them. Compliance teams should record liquidation dates and escalate affected entries promptly.

Duty recovery must also be coordinated with drawback, reconciliation, and accounting processes. If Section 301 duties were included in a drawback claim, a later PSC or protest refund may reduce the duty basis available for drawback and require adjustments. Importers should prevent duplicate recovery and maintain an auditable link among the original entry, correction, refund, and any related drawback claim.

Rejected ACE filings should be routed to the filer’s CBP Client Representative for systems troubleshooting. Questions involving trade-remedy filing requirements can generally be directed to CBP’s trade-remedy support channel at traderemedy@cbp.dhs.gov.

Frequently Asked Questions

Does Every Entry Under the New HTSUS Numbers Qualify for a Refund?

No. The revised statistical numbers help identify potential entries, but eligibility still depends on the exclusion’s product description, Chinese origin, relevant entry date, and correct filing treatment. An HTSUS match alone does not establish entitlement to a Section 301 refund.

What Is the Relevant Refund Period?

The principal review period is July 1 through September 22, 2026, when the conforming tariff language was effective but ACE had not yet activated acceptance of the revised exclusion treatment. Entries filed around noon ET on September 23 should be reviewed based on their actual transmission and duty-payment history.

Should the Section 301 Duty Number Be Reported With 9903.88.69?

Generally, no. When 9903.88.69 is properly submitted for these exclusions, the corresponding Chapter 99 number imposing the Section 301 China duties should not also be reported. Other independently applicable tariff provisions and trade-remedy requirements may still need to be declared.

Is a PSC Always the Correct Recovery Method?

A PSC is generally appropriate when the entry is unliquidated and remains within the applicable PSC timeframe. If the entry has liquidated or is otherwise ineligible for PSC treatment, a timely protest may be necessary. Entry status and deadlines should be confirmed before choosing the recovery path.

Did the Amendment Extend the Product Exclusions?

No. The amendment aligned existing exclusions with new statistical reporting numbers; it did not extend their duration. The affected exclusions remain scheduled to expire at 11:59 p.m. EDT on November 9, 2026, so importers should monitor entries near that cutoff carefully.

How Stable Software Can Help

Automating Entry Review and Refund Control

Stable Software helps importers and customs brokers identify affected entries, apply rule-based eligibility checks, and manage PSC and protest workflows across high-volume entry populations. Centralized classification data, exception queues, deadline monitoring, and document retention can reduce manual spreadsheet work while strengthening the audit trail behind each Section 301 refund claim.

The platform can also connect refund activity with duty calculations, liquidation status, broker communications, and drawback controls, helping teams avoid missed deadlines and duplicate recovery. Trade professionals can learn more about scalable customs automation and compliance workflow tools at stablesoftware.com.