A fracción arancelaria is the eight-digit code that classifies each product in Mexico's import and export tariff. That number determines the import duty you pay, the permits and standards your product has to meet, and whether you can claim the benefits of a trade agreement.
The tariff lives in Mexico's General Import and Export Tax Law (Ley de los Impuestos Generales de Importación y de Exportación, or LIGIE), published in the Official Gazette (DOF) on June 7, 2022. It isn't a fixed text: the most recent reform listed by Mexico's Chamber of Deputies is dated October 13, 2026, according to its reform history.
This guide explains how the code works. It isn't customs or tax advice: your product's classification is determined with your customs broker.
How the code is built: from chapter to NICO
Read left to right, the code goes from general to specific, and each level adds two digits:
- Chapter: the first 2 digits.
- Heading (partida): the first 4.
- Subheading (subpartida): the first 6.
- Fracción arancelaria (the Mexican tariff line): all 8 digits.
- NICO (Número de Identificación Comercial, or commercial identification number): 2 more digits that come after the fracción but are not part of it.
What matters is where each segment comes from: the first six digits come from the Harmonized System of the World Customs Organization (WCO), a nomenclature shared by its member countries; this is the "HS code" you probably already know. Digits 7 and 8, and the NICO, are national: Mexico sets them. That's how IDC Online explains it (February 10, 2023).
The practical consequence for foreign brands: the HS code your supplier or your home-country customs uses is a useful lead for the first six digits. Everything after that is Mexican, so your fracción is confirmed against Mexico's tariff, not your export paperwork.
A worked example, digit by digit
This is IDC Online's example from that guide. It shows the logic; before using any fracción on a real shipment, check the current tariff.
| Level | Code | Digits | Where it comes from |
|---|---|---|---|
| Section | IV | — | Not part of the code: it groups chapters |
| Chapter | 17 | 2 | Harmonized System (WCO) |
| Heading | 17.02 | 4 | Harmonized System (WCO) |
| Subheading | 1702.20 | 6 | Harmonized System (WCO) |
| Fracción arancelaria | 1702.20.01: Azúcar y jarabe de arce («maple») (maple sugar and maple syrup) | 8 | Mexico |
| NICO | 00 | 2 more, outside the fracción | Mexico |
Each level sits inside the one before: heading 17.02 covers subheading 1702.20, which covers fracción 1702.20.01, which opens into NICO 00. Any fracción reads the same way. If you're not sure where yours appears, see how to read an import pedimento (the pedimento is the declaration your goods enter Mexico under).
What depends on the fracción arancelaria
Three things:
| The fracción determines… | In practice |
|---|---|
| The general import duty (tariff) | The rate applied to the customs value of your goods |
| Non-tariff regulations and restrictions | Whether your product needs a permit or has to meet a NOM (Mexican Official Standard), such as the labeling ones |
| Preferential treatment | Whether you can pay less under a trade agreement, proving origin with a certificate of origin |
The fracción also decides whether a tariff measure reaches you. The decree in force since January 1, 2026 modified the duty on 1,463 fracciones for goods from countries without a trade agreement with Mexico; if your product comes from one of those countries and enters under one of those lines, it applies to you. We cover it in Mexico's tariffs on China and non-treaty countries.
Who chooses it, and who is liable
You, the importer, determine the fracción together with your customs broker (agente aduanal): the person authorized to clear your goods, who declares it on the pedimento.
Since January 1, 2026, that responsibility is shared. The Customs Law reform published in the DOF on November 19, 2025 made the customs broker and the customs agency jointly liable (responsables solidarios) with the importer for, among other things, the correct tariff classification. We break it down in what a Mexican customs broker does. That's why it's reasonable for your broker to ask for the spec sheet and composition of every product: it's their risk too.
On the authority's side, an agreement by Mexico's National Customs Agency (ANAM) published in the DOF on August 21, 2026 delegated to an internal unit the power to suggest tariff classifications. It adds no obligations for importers; we explain it in ANAM's tariff classification powers. Customs suggests; the declaration is still yours and your broker's.
A useful habit: if you import the same SKU often, check that it always enters under the same fracción. If it changes between shipments, ask why.
Where to look it up
Two official sources:
- The LIGIE text on the Chamber of Deputies website (the law as a PDF, in Spanish), along with its reform history.
- The tariff classification search tool (Buscador de fracciones arancelarias) of Mexico's Single Window for Foreign Trade (Ventanilla Única de Comercio Exterior), the government portal for foreign trade procedures.
Search by what the product is (material, composition, function), not by how you market it: "premium protective case" isn't a tariff description. When you find a candidate, take it to your customs broker with the spec sheet; the lookup gives you context, the decision is made with them.
FAQ
Is a fracción arancelaria the same as an HS code? No. The HS code is the first six digits, shared by WCO member countries. Mexico's fracción has eight: digits 7 and 8 are Mexican.
Is the NICO part of the fracción arancelaria? No. It's two additional digits after the eight of the fracción: in the example, fracción 1702.20.01 and NICO 00.
Who decides my product's fracción arancelaria? You, as the importer, with your customs broker, who declares it on the pedimento and, since January 1, 2026, is jointly liable with you for the classification.
Ecommex isn't a customs broker: we don't classify goods or file pedimentos. What we do when importing inventory into Mexico is coordinate with customs brokers, ocean carriers and truckers; receive your goods at our fulfillment center in Zapopan (Guadalajara) and count them against the commercial invoice; then store them and ship your orders.