Where are Mexico's automotive suppliers concentrated?

Automotive is Mexico's defining export industry, and its supplier base looks nothing like the rest of Mexican manufacturing. It is built around large plants, concentrated in a handful of corridors, and dominated by a few kinds of components.

This analysis covers establishments whose main activity is vehicle assembly, bodies and trailers, or motor vehicle parts (SCIAN 3361–3363), from INEGI's May 2026 directory.

A large-plant industry

Across all Mexican manufacturing, fewer than 1% of establishments have more than 250 employees. In automotive, 31.1% do. Of the 3,420 automotive establishments, 2,078 have 11 or more employees and 1,062 have more than 250.

For buyers, that cuts both ways. Mexico has a deep base of plants that already run high-volume programs under automotive quality systems. But many of the largest are tier-one suppliers or captive plants serving a specific automaker, and won't quote small or non-automotive work. Mid-size suppliers, in the 31 to 250 employee range, are often the better fit for new programs.

Five states hold half the base

Nuevo León, Guanajuato, Coahuila, Chihuahua, and Querétaro together account for 50.2% of automotive establishments with 11 or more employees.

Two corridors stand out:

• The Bajío (Guanajuato, Querétaro, San Luis Potosí, Aguascalientes) holds 29.6% of mid-size and larger automotive establishments, built around vehicle assembly plants and their suppliers.
• The northeast (Nuevo León, Coahuila, Tamaulipas) holds 26.7%, with Saltillo and Ramos Arizpe in Coahuila forming one of the densest clusters in the country.

Large plants are slightly more northern than the base overall: Coahuila has the most automotive establishments with more than 250 employees (141), followed by Guanajuato (135) and Chihuahua (125).

The top cities

Ten municipalities hold 30.2% of the country's mid-size and larger automotive establishments. Ciudad Juárez leads, followed by El Marqués, Querétaro's industrial municipality, and Silao, in Guanajuato.

What they make

Electrical and electronic equipment, which includes wire harnesses, is the single largest category, ahead of miscellaneous parts, bodies and trailers, and seats and interiors.

The data understates the supply chain in one important way: it counts establishments by their main activity. Many plants that supply automakers are classified elsewhere, for example as plastics molders, stampers, machine shops, or rubber products makers. The full automotive supply base is larger than the 3,420 establishments counted here.

What this means for buyers

• Start in the corridors. For automotive-grade components, Monterrey and Saltillo, the Bajío, and Ciudad Juárez offer the most choice within a short drive.
• Look beyond the largest plants. Mid-size suppliers are more likely to want new customers and smaller programs.
• Check certifications plant by plant. IATF 16949 certification belongs to a specific site, not to a company group. Ask for the certificate for the plant that would make your parts.
• Search by process, not just industry. Because many automotive suppliers are classified under their process, browse metal stamping, injection molding, and wire harnesses as well as automotive parts.

Methodology and limitations

Counts come from INEGI's DENUE, May 2026 release, for establishments with SCIAN activity codes beginning 3361 (vehicle assembly), 3362 (bodies and trailers), and 3363 (motor vehicle parts). Each establishment is counted once, under its main activity, so suppliers classified under other activities are not included. Corridors are groups of states defined for this analysis. Our researched profiles currently cover only a small number of automotive establishments, so this report relies on directory counts rather than verified capabilities.

How to cite. Agalma Sourcing, "Where Are Mexico's Automotive Suppliers Concentrated?," October 2026, based on INEGI DENUE (May 2026).