Before you can know how much duty you’ll pay, what VAT applies, whether you need an import permit, whether your product requires a NOM, or whether you qualify for USMCA, you have to answer one question: what tariff code does your merchandise fall under? That ten-digit number is the starting point of the entire clearance. If it’s wrong, everything downstream is wrong — and the consequences range from a fine to seized cargo.
What the tariff code is
Mexico classifies all merchandise under the TIGIE (the tariff schedule of the General Import and Export Duties Law), which in turn is built on the Harmonized System (HS) used by more than 200 countries. The structure is hierarchical:
| Level | Digits | What it defines |
|---|---|---|
| Chapter | 2 | General category (e.g. 85 = electrical machinery and equipment) |
| Heading | 4 | Type of product within the chapter |
| Subheading | 6 | Detail — these 6 digits are identical worldwide |
| Tariff line | 8 | Mexican national breakdown |
| NICO | 10 | Commercial Identification Number (fine statistics and regulation) |
The first 6 digits are universal: a laptop is 8471.30 in Mexico, China or Germany. From the seventh digit on, each country breaks it down according to its trade policy. In Mexico, since 2020, the full classification is 10 digits: 8 for the tariff line + 2 for the NICO.
Why it defines absolutely everything
The tariff code isn’t a statistical formality. It determines:
- The duty (IGI): can range from 0% to 35%+ depending on the product and origin.
- VAT: 16% general, but some lines are exempt or zero-rated.
- IEPS (excise tax): applies to certain lines (beverages, tobacco, fuels, etc.).
- Non-tariff regulations and restrictions (RRNA): prior permits, quotas, automatic notices.
- Applicable NOMs: many labeling and commercial-information NOMs are required by tariff code (see NOM labeling).
- Tariff preference under trade agreements: USMCA, EU-Mexico, CPTPP — the rule of origin is assessed at the tariff-line level.
- Specific Sector Registry: certain lines (steel, footwear, textiles, etc.) require an additional registration on top of the importer registry.
Change one digit and a 20% duty, a permit, or an unexpected NOM can appear. That’s why classification is the first real bottleneck of any new import.
How classification works (it’s not “Googling it”)
Classification is governed by the 6 General Rules of Interpretation of the Harmonized System, applied in order. In practice, classifying correctly requires:
- Knowing the product thoroughly: material, function, degree of processing, presentation, use. A “cable” isn’t the same if it’s copper, fiber-optic, with a connector, on a reel or assembled.
- Reading the Legal Notes of the chapter and heading — many exclusions and inclusions live there.
- Applying the most specific text over the generic one.
- Resolving mixtures and sets (composite goods) with rules 2 and 3.
- Documenting the criterion: technical sheets, composition, photos. If customs asks, your defense is the technical backing.
When there’s reasonable doubt, a binding tariff classification ruling can be requested from the authority before importing.
What happens when you classify wrong
| Type of error | Consequence |
|---|---|
| A code with a lower duty than the correct one | Omitted contributions → tax assessment + fine + surcharges |
| A code that skips an applicable RRNA | Held cargo, PAMA proceeding, possible seizure |
| A code that skips a NOM | Return, regularization or seizure |
| Wrong code but in good faith | Entry rectification and payment of differences |
The PAMA (Administrative Customs Procedure) is the scenario nobody wants: customs holds the goods and opens a process that can take months. A bad classification, even without intent, can leave your container stuck racking up storage charges while it gets resolved.
The most common SME mistake
Trusting classification to the foreign supplier. Your Chinese supplier sends you their 6-digit HS code — useful as a hint, but it’s not the Mexican tariff line, nor does it account for the NICO, the NOMs or Mexico’s non-tariff regulations. Importing with the code that “came on the invoice” without validating it against the TIGIE is a bet that it matches. Sometimes it does. When it doesn’t, you find out at the red light during inspection.
At TradeWay
Tariff classification is the first thing we review when a new product reaches us, before we quote the shipment — because it defines the real cost of the operation, not just the freight. We validate the tariff line and NICO against the current TIGIE, identify applicable NOMs, permits and RRNA, and verify whether you qualify for treaty preference. If your product is ambiguous, we assess with you whether a binding classification ruling makes sense. That way you avoid the surprise of an unexpected duty or a last-minute NOM that stops the container. About to import a product you’ve never brought in before? Send us the technical sheet and we’ll return the classification with its full regulatory load.
