The US Supreme Court declared illegal the reciprocal tariffs and the fentanyl tariff imposed by Donald Trump under the IEEPA. Mexico keeps zero tariffs for T-MEC compliant goods, but non-compliant ones drop from 25% to 15%. This narrows the competitive edge of non-compliant Mexican exports.
The US Supreme Court's decision, invalidating tariffs based on the International Emergency Economic Powers Act (IEEPA), signals a major shift in the trade landscape. Per the ruling, Trump cannot impose sudden tariffs without a prior Commerce Department investigation, nullifying threats against countries supporting Cuba or opposing interventions in Greenland.
In response, Trump enacted new general 15% tariffs under Section 122 of the Trade Act, a temporary tool limited to 150 days without legislative approval. For Mexico, T-MEC compliant goods retain zero tariffs, covering about 83% of its exports to the US. However, the remaining 17% now faces 15%, down from 25%, aligning with similar rates for the European Union (from 20% to 15%), China (from 34% to 15%), and Vietnam (from 46% to 15%). Canada keeps exemptions under the regional agreement.
Mexico solidified in 2025 as the top US trade partner, accounting for 15.6% of its total trade, with Mexican exports up 5.81% to a volume of 872.8 billion dollars. Yet, tariffs persist in key sectors like steel, aluminum, vehicles, and auto parts, where Mexico has strong presence.
Analysts foresee litigation over Section 122's validity and potential shifts to tools like Section 301 for sectoral actions. This could expose competitive Mexican industries such as automotive and electronics. Stability hinges on operational precision and full T-MEC utilization to avoid the 15%.
