Mexico IEEPA Tariffs: What Importers Need to Know

Overview

Mexico is the largest U.S. trading partner, with roughly $800 billion in bilateral trade in 2024. The most heavily traded categories include vehicles and auto parts, machinery and electronics, agricultural products, and oil and energy products. Because of the volume and variety of goods crossing the border, the IEEPA tariffs affected a wide range of importers.

Starting March 4, 2025, the federal government imposed an additional 25% duty on all Mexico-origin imports under the International Emergency Economic Powers Act. This was layered on top of existing duties -- meaning importers paid their normal tariff rate plus the 25% IEEPA surcharge. A major exception: goods qualifying for preferential treatment under USMCA (the U.S.-Mexico-Canada Agreement) were exempt, which covered a significant share of Mexico-origin trade.

The 25% IEEPA rate remained in effect for nearly a full year. During that period, CBP also clarified carveouts for potash, energy products, humanitarian donations, and informational materials. The IEEPA tariff ended on February 24, 2026, following the Supreme Court's ruling in Learning Resources v. Trump.

On the same day the IEEPA tariff ended, a new Section 122 surcharge of 10% took effect for most countries, including Mexico. USMCA-qualifying goods remain exempt under Section 122 as well. For importers who paid the 25% IEEPA duty on non-exempt goods, the key question now is whether those payments may be recoverable.

Informational only — not legal advice.

What Changed: Rate Timeline

Exceptions and Carveouts

Not every Mexico-origin import was subject to the full 25% IEEPA rate. The following exceptions applied during the IEEPA collection window.

If your goods qualified under one of these exceptions, the IEEPA surcharge either did not apply or applied at a lower rate. USMCA eligibility was the most common path to exemption.

What This Means for Your Refund

If you imported non-exempt goods from Mexico between March 4, 2025 and February 24, 2026, you may have paid an additional 25% in IEEPA duties on top of your normal tariff rate. Following the Supreme Court's ruling in Learning Resources v. Trump, those duties may be refundable.

The type of filing depends on your entry's liquidation status:

• Unliquidated entries may be corrected through a Prior Disclosure or Post-Summary Correction (PSC)
• Liquidated entries typically require a Form 19 protest, which must be filed within 180 days of liquidation

IEEPA duties are separate from Section 232 duties and Section 301 duties. Those programs are not affected by the Supreme Court ruling.

If you are unsure whether your entries qualify, check the full Chapter 99 line, not just the ordinary HTS. Mexico’s IEEPA program uses 9903.01.*, while other IEEPA lanes can also use 9903.02.*.

Chapter 99 Code Reference

This section is for customs brokers, trade compliance teams, and anyone reviewing entry summaries at the line-item level. Each Chapter 99 code corresponds to a specific IEEPA or Section 122 treatment.