New Order for Stacking Tariffs Starting June 4

On June 3, 2025, the President signed a proclamation on Adjusting Imports of Aluminum and Steel in the United States, which resulted in an update to tariff stacking rules. U.S. Customs and Border Protection (CBP) provided updated guidance on the new priority stacking order effective June 4, 2025.

The largest change is the IEEPA Canada and IEEPA Mexico tariffs moved down the list after Section 232 Steel and Aluminum tariffs.

New Priority Order

Effective with respect to goods entered for consumption, or withdrawn from warehouse for consumption, on or after 12:01 a.m. EDT on June 4, 2025, below is the new priority order of the five presidential actions identified in EO 14289, as amended:

• Section 232 – Automobile and Auto Parts
• Section 232 – Aluminum
• Section 232 – Steel
• IEEPA Canada
• IEEPA Mexico

Applicability Order

Section 232 – Automobile and Auto Parts

Articles subject to the Section 232 Automobile and Auto Parts tariffs shall not be subject to additional tariffs:

• Section 232 Aluminum
• Section 232 Steel
• IEEPA Canada
• IEEPA Mexico

Section 232 Aluminum & Steel

If an article is not subject to the 232 Auto/Auto Parts tariff, and is subject to Section 232 Aluminum and/or Section 232 Steel tariffs.

-Articles subject to both Section 232 Aluminum and Steel tariffs, duties will be owed on both the value of the aluminum and steel content of that product.

-Articles subject to Section 232 Aluminum and/or Steel tariffs shall not be subject to additional tariffs:

• IEEPA Canada
• IEEPA Mexico

NOTE:  Aluminum and aluminum derivative products from Russia, and imports of such aluminum products from any country containing aluminum smelt or cast in Russia, ARE subject to the corresponding Section 232 duty rate of 200 percent.

NOTE:  Articles that qualify for preferential tariff treatment under USMCA, ARE NOT subject to the IEEPA Canada or IEEPA Mexico tariffs. 

Example Reporting

For purposes of the five tariff measures included in EO 14289, filers are to report the appropriate Chapter 99 number(s) (a) that corresponds to the additional duties due and (b) that corresponds to the USMCA exemption, if applicable.  For example:

Passenger vehicles and light trucks from Japan –

• Report 9903.94.01 / 25 percent (232 Autos)

Steel auto part from Canada that qualify for preferential treatment under USMCA –

• Report USMCA 9903.94.06 (0%)
• Report 50 9903.81.91 / 50 percent (232 Steel)

Steel from Canada that does not qualify for preferential treatment under USMCA –

• Report 9903.81.87 / 50 percent (232 Steel)

Reporting requirements for tariffs outside of EO 14289 are not changed.

FAQ

Is this Executive Order retroactive?

No. This updated tariff stacking order takes effect on June 4, 2025.

What other tariffs can a product be subject to?

Here is a list of additional duties, but not limited to:

• General rate of duty (column 1 of the Harmonized Tariff Schedule of the United States (HTSUS))
• Section 301 China
• IEEPA China
• Antidumping and countervailing duties

Have Questions? Contact your local NNR Representative.

We will continue to monitor this tariff action and provide updates as they become available.