9903.01.01 (Ended): IEEPA Mexico Fentanyl 25% Tariff Heading

Key Points

• HTS heading 9903.01.01 imposed a 25 percent ad valorem duty on most articles the product of Mexico under the IEEPA Mexico Fentanyl program, effective 2025-03-04 through 2026-02-23.
• The heading ended on 2026-02-24 and was no longer in force as of the article's as-of date of October 19, 2026.
• Products described in companion headings 9903.01.02, 9903.01.03, 9903.01.04, and 9903.01.05 were excluded from 9903.01.01's scope.
• The legal authority was Executive Order 14194, as amended.
• Duties deposited under 9903.01.01 may be refundable through CBP's CAPE process in ACE; importers need their entry numbers, 7501 lines, and liquidation status to prepare a claim.

On this page

1. What 9903.01.01 was and when it ended
2. Products and countries in scope
3. The 25 percent rate and its effective window
4. Exemption headings and how they interacted with 9903.01.01
5. How the heading appeared on a customs entry
6. Refund path for duties deposited under 9903.01.01
7. What importers should do
8. Key references

HTS heading 9903.01.01 was a Chapter 99 special-program code that added a 25 percent duty to most articles the product of Mexico, authorized by Executive Order 14194, as amended. It was active from 2025-03-04 through 2026-02-23 and ended on 2026-02-24. It is no longer in force. The links throughout this article go to the primary documents: the executive order, the official tariff schedule, and CBP guidance pages themselves. Read the source.

What 9903.01.01 was and when it ended

Heading 9903.01.01 was created under the International Emergency Economic Powers Act (IEEPA) as part of the Mexico Fentanyl program. The legal basis was Executive Order 14194, as amended. The heading's official text read: "Except for products described in headings 9903.01.02, 9903.01.03, 9903.01.04 and 9903.01.05 articles the product of Mexico, as provided for in U.S. note 2(a) to this subchapter."

The heading was active for just under one year. It took effect on 2025-03-04 and its final day of applicability was 2026-02-23. As of 2026-02-24, the heading was terminated and is no longer in force. Entries filed on or after 2026-02-24 did not carry this heading.

Products and countries in scope

9903.01.01 applied exclusively to articles the product of Mexico. No other country of origin triggered this heading. The scope was broad: subject to the exclusions described below, the heading covered the general universe of Mexican-origin merchandise as provided for in U.S. note 2(a) to the Chapter 99 subchapter in force during the applicable window.

Importers needed to confirm country of origin under CBP's substantial-transformation standard. Goods that merely transited Mexico, or that were processed there without a substantial transformation, were not necessarily "products of Mexico" for tariff purposes. Confirm the applicable origin rules in the HTSUS or with your broker if origin was in question.

The 25 percent rate and its effective window

The duty rate imposed by 9903.01.01 was 25 percent ad valorem. That rate applied to all in-scope Mexican-origin goods entered for consumption, or withdrawn from warehouse for consumption, from 2025-03-04 through 2026-02-23. The heading imposed an additional duty on top of the normal column 1 general rate for the underlying Chapter 1-97 classification; the two rates stacked.

No rate other than 25 percent applied under this specific heading. The facts block does not identify any phased reduction or escalation within the window, so importers should treat the 25 percent as flat across the entire operative period.

Exemption headings and how they interacted with 9903.01.01

Four companion headings carved out specific categories of Mexican-origin goods from 9903.01.01's reach:

• 9903.01.02
• 9903.01.03
• 9903.01.04
• 9903.01.05

Products that fell within any of those four headings were excluded from 9903.01.01 by the heading's own text. If a product was described in one of the companion headings, the 25 percent rate did not apply through 9903.01.01. Importers should check the current HTSUS Chapter 99 and the companion heading articles (see Key references) to understand what each exemption covered. The facts block does not detail the scope of 9903.01.02 through 9903.01.05, so confirm their precise text in the HTSUS or with your broker.

For a closely parallel program involving Canadian-origin goods, see the related article on 9903.01.10 (Ended): IEEPA Canada Fentanyl Tariff Heading Explained.

How the heading appeared on a customs entry

Chapter 99 codes like 9903.01.01 rode alongside, not instead of, the underlying Chapter 1-97 classification. On a CBP Form 7501, a dutiable Mexican-origin entry looked like this in practice:

• Line 1: The substantive HTS number from Chapters 1-97 carrying the column 1 general rate.
• Line 2 (or same line, additional code): 9903.01.01, triggering the additional 25 percent.

Both duties were computed on the entered value and added together. If the companion exemption headings applied, the broker would have reported the relevant exemption heading (9903.01.02, .03, .04, or .05) instead of 9903.01.01. Entries that omitted 9903.01.01 for in-scope Mexican goods during the 2025-03-04 to 2026-02-23 window may have been under-declared and could face CF-28 or CF-29 requests from CBP.

For a broader look at how Chapter 99 codes were organized in 2026, see the 2026 tariff code overview.

Refund path for duties deposited under 9903.01.01

Because 9903.01.01 was an IEEPA heading, duties deposited while it was in force were refundable through CBP's CAPE (Customs Automated Protest and Entry) process in ACE. The heading ended on 2026-02-24, so duties collected during the 2025-03-04 through 2026-02-23 window are the amounts in question.

To prepare a claim, an importer needed:

• Entry numbers for every affected shipment.
• The 7501 lines that carried the 9903.01.01 heading and the associated duty amounts.
• Each entry's liquidation status, because unliquidated entries and liquidated entries follow different procedural tracks in CAPE.

The step-by-step process for pursuing a refund is on the IEEPA tariff refund guide. Common reasons CAPE submissions are rejected, and how to fix them, are covered on the CAPE errors page. If you use ACE to manage your entry data, the article on the ACE Portal application and account setup explains what data is accessible and how to pull the records you need.

What importers should do

• Audit your entry records for all Mexican-origin shipments entered between 2025-03-04 and 2026-02-23 to confirm whether 9903.01.01 was correctly reported or, if an exemption heading applied, correctly excluded.
• Gather entry numbers, 7501 line data, and liquidation status for any entries that carried the 25 percent duty, then follow the CAPE refund process outlined at /articles/ieepa-tariff-refund-guide before your protest deadlines run.
• Consult the current HTSUS and confirm with your broker that no successor heading or active duty provision now applies to your Mexican-origin goods, since the facts block is silent on any replacement program.
• Review your continuous bond exposure for the affected period with your surety; see Customs Bond Types: Continuous, Single Transaction, and ISF Bonds for background on how bond amounts relate to duty liability.

Key references

• Executive Order 14194 (White House) - The legal authority that created the Mexico Fentanyl IEEPA tariff program.
• Harmonized Tariff Schedule of the United States (USITC) - Official text of heading 9903.01.01 and companion headings 9903.01.02 through 9903.01.05.
• CBP.gov - CBP guidance, CSMS messages, and the CAPE protest portal for entry corrections and refund claims.
• Federal Register (federalregister.gov) - Notices and rules implementing EO 14194 and subsequent amendments.
• IEEPA Tariff Refund Guide (CustomsGenius) - Step-by-step instructions for filing a CAPE refund claim for duties deposited under an IEEPA heading.
• CAPE Errors (CustomsGenius) - Common CAPE submission rejections and how to resolve them.
• 9903.01.10 (Ended): IEEPA Canada Fentanyl Tariff Heading Explained - Parallel program for Canadian-origin goods under the same IEEPA authority.
• 2026 Tariff Code Overview (CustomsGenius) - How Chapter 99 special-program codes were structured in the 2026 HTSUS.