Mexico's retaliatory tariff on US Steel & Iron Products exports

Mexico’s twenty-five percent surtax on US steel is the industrial counterpart to its headline corn measure — a more conventional, proportionate response to the US Section 232 steel duty, paired in the same March 2025 package with the far steeper agricultural charge. It applies to US-origin steel flat products under Harmonised System heading 7208.52 and related Chapter 72 lines, and took effect March 15, 2025, the same date as the corn surtax.

Although the rate matches Canada’s steel surtax, the Mexican measure differs in its legal architecture, and the difference matters for anyone tracking it. Where Canada acts through a numbered Surtax Order published in the Canada Gazette under its Customs Tariff, Mexico imposes its charge by presidential Decreto published in the Diario Oficial de la Federación and administered by the Secretaría de Economía. A Decreto carries immediate legal force on publication, without the separate regulatory instrument and the discrete order number that characterise the Canadian approach. The rate recorded here is verified through the ITA Foreign Retaliations Database; the exact Decreto reference is being confirmed against the Diario Oficial in a later legal review, so the gazette is named as the authority of record rather than linked directly.

A second difference is what has nothappened. Canada’s steel surtax was substantially rolled back for CUSMA-qualifying goods in September 2025; Mexico’s steel measure carries no equivalent removal event in the record and remains in force as recorded. Like the corn charge, however, it is structured to target shipments that do not qualify under the Canada-United-States-Mexico Agreement, so a US exporter able to establish USMCA-qualifying origin is treated differently from one that cannot — a posture that broadly parallels the Canadian exemption structure even though the legal route to it is Mexico’s own.

For a US steel producer selling flat products into Mexico, the practical priorities are to confirm the heading classification of each product against the covered Chapter 72 lines, determine whether the shipment can establish USMCA-qualifying status, and verify the live rate before pricing — recognising that because the charge flows from a decree that can change on publication, the duty environment is less predictable than one governed by a slower, notice-based process. Forward contracts into the Mexican market should allocate tariff risk explicitly rather than assume the twenty-five percent rate is fixed.

See also: Mexico tariff overview, Steel & Iron Products, and Mexico’s full retaliation list.