15 versus 19: the tariff that separates a Japanese car made in Japan from one made in the Bajío

Bajío Ventures · June 2026 · Japan in the Bajío, 4 of 5

Japanese automakers came to the Bajío to export to the United States under the North American free trade agreement. Since 2025 the rule has changed: a Japanese car made in Japan pays a lower US tariff than one made in Mexico.

Three rules that cross

Rule	From	What it says
US Section 232 (autos)	3 April 2025	25% on imported vehicles. If the vehicle qualifies under USMCA, the 25% applies only to its non-US content. Parts from 3 May 2025.
US–Japan tariff deal	16 September 2025	Japanese vehicles pay a flat 15%.
Mexico’s new tariffs	1 January 2026	1,463 tariff lines rise to between 10% and 50% for countries without a trade agreement with Mexico; vehicles and parts are in the top band. Japan is excluded because it has had a trade agreement with Mexico since 2005.

The result: 15 versus 19

Mexican officials have shown Washington that the average tariff on Mexico’s automotive exports to the United States is about 19%, above the 15% paid by cars made in Japan or Korea. For a Japanese automaker, the Bajío plant is no longer the cheapest route to the US consumer.

In the Mexican market the opposite happens. Mexico’s new tariffs hit cars imported from Korea, China, India or Thailand, but not Japanese ones. In Mexico, the Japanese brand gains an edge.

What the automakers did

• Mazda was the most exposed. In the second quarter of 2025 it cut US shipments by 53.4%. For the year, its Salamanca output fell 16.6% and its exports 37.6%. US sales of the Salamanca-built CX-30 fell from 96,515 units in 2024 to 56,684 in 2025. In January 2026, Mazda confirmed it will keep building the Mazda2, CX-3 and CX-30 in Guanajuato.
• Honda denied in April 2025 that it had decided to move production from Celaya to the United States; in 2024, 85% of Celaya’s HR-Vs were exported there. It did decide to build the next-generation Civic, which had been planned for Celaya, in Indiana from 2028.
• Nissan closed CIVAC in March 2026 under its global Re:Nissan plan and concentrated its Mexican output in Aguascalientes.
• Toyota grew 44.7% in Apaseo el Grande with the Tacoma, a pickup in high demand in the United States.

In December 2025, compared with December 2024, exports fell 73.9% at Mazda, 47.7% at Nissan and 45.5% at Honda; Toyota’s rose 29.4%. Mexico exported 3,385,785 light vehicles in 2025, 2.7% fewer than in 2024.

The USMCA review

The first formal round of the USMCA review took place in Mexico City on 28 and 29 May 2026; the second, in Washington, on 16 and 17 June. The United States kept the Section 232 tariffs on autos, steel and aluminium. According to press reports, Washington wants to raise regional content for vehicles; Mexico rejected the proposal. The joint review of the agreement is set for 1 July 2026.

The reading

• Japanese volume in the Bajío now depends on the model, not only the plant. A pickup in demand in the US (Tacoma) grows; a subcompact SUV with substitutes (CX-30) falls.
• The Mexican market gains weight. With high tariffs on cars from countries without a trade agreement, the Bajío’s Japanese plants have a domestic-market advantage they did not have before 2026.
• US and regional content becomes a cost variable. Every point of US content lowers the Section 232 tariff. That pushes suppliers to review where they buy.
• For an infrastructure investor, the plant with the most certainty is the one running near capacity with a product the tariff does not punish. That is the easiest energy demand to finance.

In this series: 1. Forty years of Japan in the Bajío · 2. The Bajío’s Japanese automakers by the numbers · 3. 150 Japanese companies: the Bajío supply base · 4. 15 versus 19: the tariff · 5. Powering the Bajío’s Japanese plants

Bajío Ventures is a Mexican energy infrastructure investment group based in Guanajuato. We originate and structure USD 5–50 million projects across the Bajío corridor.

This analysis is not legal or trade-compliance advice.

Sources: C.H. Robinson, Section 232 tariffs on autos and parts, Mar 2025 · International Trade Insights, Japanese tariff reductions from 16 September 2025 · Clark Hill, Mexico’s new tariffs on non-FTA countries, Dec 2025 · Bloomberg Government, Mexico and Korea’s better deal, Jun 2026 · Mexico Business News, US shipment cuts, Aug 2025 · Mexico Business News, 2025 output and exports · Jalopnik, CX-30 sales, Jan 2026 · Cluster Industrial, Mazda stays in Guanajuato, Jan 2026 · Expansión, Honda denies production move, Apr 2025 · Mexico News Daily, next Civic goes to Indiana, Apr 2025 · WardsAuto, CIVAC closure, Jul 2025 · UnoTV, 2025 light-vehicle exports · Zeta Tijuana, formal USMCA review begins, May 2026 · La Política Online, first round of the USMCA review, May 2026