The Tariff Tool Most Manufacturers in Mexico Overlook: How PROSEC Cuts Input Costs to 0-5%

PROSEC, Mexico's Programa de Promocion Sectorial, lets manufacturers import production inputs at preferential duty rates of 0% to 5% regardless of the country of origin. It covers 24 strategic industrial sectors. It does not require goods to be exported. And most US companies operating in Mexico either do not know it exists or do not understand how it interacts with IMMEX.

That gap costs real money. Here is how the program works, who qualifies, and why it matters more in 2026 than it ever has.

What PROSEC actually does

Mexico's standard MFN (Most Favored Nation) tariff rates on industrial inputs range from 5% to 35%, depending on the product. For manufacturers registered under PROSEC, those rates drop to 0% to 5% on qualifying inputs tied to their registered sector.

The mechanism is straightforward. A manufacturer registers with the Ministry of Economy under one or more of PROSEC's 24 sector categories. Once approved, that manufacturer can import raw materials, components, and intermediate goods listed under their sector's tariff schedule at the preferential PROSEC rate. The savings apply whether the finished goods are exported or sold domestically in Mexico.

This is the critical distinction from IMMEX. IMMEX defers duties on imports that will be re-exported. PROSEC reduces duties on imports used in manufacturing regardless of the final destination. They solve different problems, and they work together.

The 24 PROSEC sectors

PROSEC covers a specific list of industrial sectors, each with its own eligible input schedule:

• Electrical
• Electronics
• Furniture
• Toys and sporting goods
• Footwear
• Mining and metallurgy
• Capital goods
• Photography
• Agricultural machinery
• Various industries
• Chemicals
• Rubber and plastics
• Steel
• Pharmaceutical and medical equipment
• Transportation (except automotive)
• Paper and cardboard
• Timber
• Leather and hides
• Automotive and auto parts
• Textiles and apparel
• Chocolate, sweets, and similar
• Coffee
• Food industry
• Fertilizers

If your manufacturing operation falls within any of these sectors, PROSEC likely covers a substantial portion of your imported input bill.

Why PROSEC matters more in 2026

Three forces converged to make PROSEC unusually valuable this year.

Mexico's new tariffs on non-FTA imports. Effective January 1, 2026, Mexico imposed sweeping tariffs on 1,463 tariff lines from countries without free trade agreements: 50% on passenger automobiles, roughly 35% on auto parts, textiles, plastics, and steel. A manufacturer importing Chinese plastic resin into Mexico now faces a 35% tariff at the border. Under PROSEC, that same resin enters at 0% to 5%.

The savings are enormous. On a $500,000 annual resin purchase from China, the difference between a 35% standard rate ($175,000 in duties) and a 3% PROSEC rate ($15,000) is $160,000 per year. That single line item can determine whether a Mexico operation is viable.

The Hormuz crisis raised global input costs. Petrochemical feedstock prices spiked 30% to 43% depending on the commodity since the Strait of Hormuz closed on March 2. PROSEC does not fix global commodity prices, but it prevents Mexico's tariff structure from compounding the damage. Paying 0% to 5% duty on an input that already costs 40% more is survivable. Paying 35% duty on top of a 40% commodity spike is not.

USMCA compliance pressure is accelerating. USMCA utilization among Mexican exporters jumped from 44.8% in January 2025 to 88.7% by November. Hundreds of companies are newly navigating rules of origin for the first time. PROSEC-imported inputs can count toward USMCA regional value content calculations when they are substantially transformed in Mexico.

How PROSEC and IMMEX work together

The most powerful cost structure in Mexican manufacturing combines both programs.

For goods being exported: Import inputs under IMMEX. Duties are deferred entirely. The goods are manufactured in Mexico and shipped to the US or another market. No Mexican import duty is ever paid.

For goods sold domestically in Mexico: When an IMMEX-registered manufacturer sells finished goods into the Mexican domestic market, those goods "change customs status." The deferred duties on the imported inputs become payable. This is where PROSEC saves money. Instead of paying the full MFN rate (potentially 35% on Chinese-origin inputs), the manufacturer pays the PROSEC preferential rate of 0% to 5%.

The combined strategy: A manufacturer registers under both IMMEX and PROSEC. Export production runs through IMMEX with full duty deferral. When domestic sales opportunities arise, the manufacturer invokes PROSEC rates on the customs status change. This flexibility to serve both export and domestic markets without prohibitive duty costs is what makes the dual registration valuable.

The catch: tracking which inputs are under IMMEX deferral and which have been converted to PROSEC status requires precise inventory management and customs documentation. The new January 2026 customs law dramatically increased documentation requirements, penalties, and real-time inventory tracking obligations. Over 600 IMMEX programs were suspended in 2025 due to compliance issues. Getting this wrong is expensive.

Who qualifies and how to register

PROSEC registration requires a manufacturer operating in Mexico with a valid tax ID (RFC) and active operations in one or more of the 24 covered sectors. The application goes through the Ministry of Economy (Secretaria de Economia). Processing typically takes 15 to 30 business days.

• Active IMMEX program (for manufacturers also exporting)
• Valid RFC and current tax compliance certificate
• Proof of manufacturing operations in Mexico
• Sector-specific documentation showing imported inputs are used in production

A licensed customs broker (agente aduanal) is essential for both the registration process and ongoing compliance. The agente aduanal files the import pedimentos (customs declarations) that invoke PROSEC rates and maintains the documentation trail that Mexican customs authorities (ANAM) will audit.

The bottom line

PROSEC saves 30 to 35 percentage points on import duties for qualifying manufacturers in Mexico. In a year when global input costs are spiking, Mexico's own tariffs on non-FTA imports are at historic highs, and USMCA compliance pressure is intensifying, those savings are not optional. They are the difference between a competitive cost structure and an unworkable one.

The program is available. The savings are documented. The risk is in the classification and compliance execution. Get the HS codes right, get the PROSEC registration aligned to your actual inputs, and get a customs broker who understands the IMMEX interaction. The tariff math does the rest.