CBP Issues Guidance on Tariff Stacking Under Executive Order 14289

With the introduction of a single-duty rule and refund options for overlapping tariffs that were paid, this policy provides stronger oversight, greater predictability, and improved cost control for U.S. importers.

U.S. Customs and Border Protection (CBP) has issued new guidance (CSMS #65054270) implementing Executive Order 14289, which addresses the issue of tariff stacking.

Tariff stacking occurs when imported goods are subject to multiple overlapping duty programs.

With the aim of avoiding redundant charges and simplifying compliance for U.S. importers, this Executive Order (EO) establishes a standardized order of application to ensure that only the highest-priority tariff is imposed.

Tariff programs that are covered

The EO applies when a product may fall under more than one of the following five measures:

• Section 232 Auto/Auto Parts Tariffs: Proclamation 10908 of March 26, 2025 (Adjusting Imports of Automobiles and Automobile Parts into the United States), as amended;
• IEEPA Canada Tariffs: Executive Order 14193 of February 1, 2025 (Imposing Duties to Address the Flow of Illicit Drugs Across Our Northern Border), as amended;
• IEEPA Mexico Tariffs: Executive Order 14194 of February 1, 2025 (Imposing Duties to Address the Situation at Our Southern Border), as amended;
• Section 232 Aluminum Tariffs: Proclamation 9704 of March 8, 2018 (Adjusting Imports of Aluminum into the United States), as amended; and
• Section 232 Steel Tariffs: Proclamation 9705 of March 8, 2018 (Adjusting Imports of Steel into the United States), as amended.

New tariff application hierarchy

CBP’s guidance directs importers to apply additional duties in a specific order of precedence when goods are subject to more than one of the five trade actions listed above.

This hierarchy ensures that only one of the five applicable duties is imposed—based on eligibility and exemption.

1. Section 232 Auto/Auto Parts Tariffs

This duty takes precedence over all others. If an article is subject to the Section 232 Auto/Auto Parts tariff, no other additional duties from the remaining four actions apply.

However, vehicle parts that qualify under the United States-Mexico-Canada Agreement (USMCA) are not subject to this duty or to the International Emergency Economic Powers Act (IEEPA) tariffs.

2. IEEPA Canada or Mexico Tariffs

If the auto tariff is not applicable, and the article is subject to an IEEPA measure—under either EO 14193 (Canada) or EO 14194 (Mexico)—it will be assessed under that tariff instead of the aluminum or steel duties.

Articles qualifying for USMCA preferential treatment are not subject to IEEPA Canada or Mexico tariffs.

3. Section 232 Aluminum and Steel Tariffs

If the article is not subject to either of the above tariffs but is subject to Proclamation 9704 (aluminum) and/or Proclamation 9705 (steel), then these duties are assessed.

In cases where an article contains both aluminum and steel derivatives subject to Section 232, duties must be paid on both components.

Aluminum and derivative articles that are of Russian origin or contain Russian-origin aluminum are subject to a 200% ad valorem duty rate under Section 232. 

Other duties still apply

The new tariff hierarchy does not eliminate other applicable duties. Importers must still account for other tariffs, including but not limited to:

• Rates outlined in columns 1 or 2 of the Harmonized Tariff Schedule of the United States (HTSUS).
• Tariffs imposed by Section 301 of the Trade Act of 1974, as amended.
• Duties imposed by EO 14195 (Imposing Duties To Address the Synthetic Opioid Supply Chain in the People's Republic of China).
• Antidumping and countervailing duties.

Reporting requirements

Importers must report all relevant Chapter 99 HTSUS numbers reflecting:

• The applicable additional duties due.
• Exemptions under USMCA, if applicable.

Examples:

• A Canadian-origin steel product not eligible under USMCA must be reported under 9903.01.10 (IEEPA Canada).
• A Canadian steel article eligible under USMCA should be reported under both 9903.81.87 (Section 232 Steel) and 9903.01.14 (IEEPA Canada exemption under USMCA).

Reporting requirements for tariffs outside of EO 14289 remain unchanged.

Refunds and retroactive claims

Importers who paid duties under multiple overlapping tariff programs for covered articles entered for consumption (or withdrawn from warehouse for consumption) on or after March 4, 2025, may be eligible for refunds under EO 14289. 

Refunds are permitted only when duties were collected contrary to the stacking hierarchy established in EO 14289.

In such cases, importers may recover only the duties that are no longer due under the new prioritization rule.

To request a refund, you will need to submit the following:

• A post summary correction (PSC) for unliquidated entries.
• A protest under 19 U.S.C. §1514 for liquidated entries within the 180-day protest window.

Refund claims may be submitted beginning May 16, 2025.

It is important to note that no refunds will be issued for duties paid under the Section 232 Auto/Auto Parts tariff, as this measure is at the top of the tariff hierarchy and always applies when relevant.

Next steps for U.S. importers

If your shipments are affected by more than one duty program, we advise that you do the following:

• Review recent entries made on or after March 4, 2025, to identify any duty overpayment.
• Confirm duty treatment based on the hierarchy set in EO 14289.
• Check USMCA eligibility to determine applicable exemptions.
• Coordinate with your customs broker to file post summary corrections or protests where applicable. 

How Cole International can help

At Cole International, we constantly monitor changing trade regulations and offer customs and compliance consulting services to help businesses navigate these changes.

Additionally, we provide timely and efficient customs brokerage services to help U.S. importers streamline their customs clearance and other import processes.

Please reach out to one of our trade professionals to discuss the impact of tariff stacking on your business and how we can help you avoid overpaying on your duties.