Mexico — Tariff Classification

Mexico's tariff classification framework rests on two federal statutes administered by agencies within the Secretaría de Hacienda y Crédito Público (Ministry of Finance): the Ley de los Impuestos Generales de Importación y de Exportación (LIGIE) and the Ley Aduanera (Customs Law).

The LIGIE and the TIGIE tariff schedule. Article 1 of the LIGIE establishes the tariff rates (cuotas) applicable to the classification of merchandise (clasificación de la mercancía) for purposes of determining import and export duties. The tariff schedule itself is known as the Tarifa de la Ley de los Impuestos Generales de Importación y de Exportación (TIGIE). The current version of the LIGIE was enacted by decree published in the Diario Oficial de la Federación on June 7, 2022, and implemented the Seventh Amendment to the World Customs Organization (WCO) Harmonized System effective January 1, 2022. Mexico updates the TIGIE periodically to align with amendments to the Harmonized System; the WCO Harmonized System Committee issues amendments (called enmiendas) approximately every five years.

Harmonized System foundation. Mexico is a party to the International Convention on the Harmonized Commodity Description and Coding System (the Harmonized System Convention). Mexican tariff classification uses an eight-digit structure: the first six digits follow the international Harmonized System nomenclature administered by the WCO, and Mexico adds two national-level digits (the seventh and eighth) to create fracciones arancelarias (tariff items). Importers and exporters must classify merchandise at the eight-digit fracción arancelaria level.

General Rules for Interpretation. Article 2, Section I of the LIGIE sets out the Reglas Generales (General Rules) for the application and interpretation of the tariff (Reglas Generales para la aplicación e interpretación de la Tarifa). These rules mirror the six General Rules for the Interpretation of the Harmonized System (GRI 1 through GRI 6) established by the WCO. The General Rules govern the methodology for classifying goods: GRI 1 (classification by heading text and section/chapter notes), GRI 2(a) (incomplete or unfinished articles), GRI 2(b) (mixtures and combinations of materials), GRI 3 (goods prima facie classifiable under two or more headings, resolved by essential character under GRI 3(b) or by the heading which occurs last in numerical order under GRI 3(c)), GRI 4 (classification of goods not covered by the preceding rules), GRI 5 (packing materials and containers), and GRI 6 (classification at the subheading level). The LIGIE also incorporates Notas Explicativas de Aplicación Nacional (national explanatory notes) to aid interpretation of specific headings and fracciones arancelarias.

Administering authorities. The Servicio de Administración Tributaria (SAT), a decentralized agency of the Secretaría de Hacienda y Crédito Público, administers customs operations and enforces the LIGIE and the Ley Aduanera. Within SAT, the Agencia Nacional de Aduanas de México (ANAM) exercises operational authority over Mexico's customs offices (aduanas). The Secretaría de Economía maintains the official online tariff database (SNICE - Sistema de Información de Comercio Exterior) and coordinates updates to the TIGIE. Importers may request a binding advance classification ruling (consulta sobre clasificación arancelaria) from SAT under Rule 1.2.8 of the Reglas Generales de Comercio Exterior (General Rules of Foreign Trade); SAT rulings are binding on the importer and the customs authority with respect to the specific merchandise described.

Interaction with the Ley Aduanera. The Ley Aduanera governs the procedural aspects of customs clearance (despacho aduanero), including entry declarations, documentary requirements, verification (verificación), and penalties for incorrect classification. Article 1 of the Ley Aduanera provides that the LIGIE, the Ley Aduanera, and other applicable laws jointly regulate the entry and exit of merchandise from Mexican territory. Article 4 of the Ley Aduanera requires that customs brokers (agentes aduanales) holding a patent from the Secretaría de Hacienda y Crédito Público perform or supervise the classification and customs clearance of commercial shipments. Misclassification can trigger penalties under the Ley Aduanera and result in retroactive duty assessments and interest charges.

Source: Ley de los Impuestos Generales de Importación y de Exportación, Arts. 1, 2 Source: Ley Aduanera, Arts. 1, 4 Source: SNICE – LIGIE Information (Secretaría de Economía)

Mexico's advance classification ruling procedure allows importers, exporters, customs brokers, and trade associations to obtain a binding determination from SAT on the correct tariff classification and número de identificación comercial (NICO) before importing or exporting merchandise. The ruling binds both the applicant and the customs authority for future operations involving the described merchandise, reducing the risk of retroactive duty assessments and penalties.

Two types of rulings under Article 47 of the Ley Aduanera. The first paragraph of Article 47 establishes a ruling for cases in which the applicant believes the merchandise could be classified under more than one tariff heading or fracción arancelaria. In these cases, the applicant must propose a classification and explain the legal reasoning supporting that classification, identify the alternative headings under consideration, and attach samples, catalogs, technical specifications, photographs, or other materials that allow full identification of the merchandise. The last paragraph of Article 47 permits a ruling when the applicant does not know the classification at all; this type of ruling is governed by Article 34 of the Código Fiscal de la Federación and requires the applicant to state that the purpose is to obtain the classification the authority determines. Both types of ruling must be filed prior to the trade operation.

Eligible applicants. Importers, exporters, customs brokers (agentes aduanales), authorized representatives (apoderados aduanales), confederations, chambers, and associations may request a ruling. The request may be filed online through the SAT portal (Trámite de Clasificación Arancelaria in the Buzón Tributario) or in paper form before the Administración Central de Normatividad en Comercio Exterior. The written request must comply with the general requirements of Articles 18, 18-A, and 19 of the Código Fiscal de la Federación: name or corporate name and domicilio fiscal, the requesting authority, contact telephone numbers, a domicilio for receiving notifications, the taxpayer's RFC, a description of the applicant's activities, and a statement of facts and circumstances. The applicant must identify the proposed tariff heading and NICO (if known), provide the reasoning that supports the proposed classification, state which alternative headings are in doubt, and attach materials (samples, catalogs, data sheets, labels, photographs, blueprints, brochures, diagrams) that permit full identification of the merchandise.

Laboratory-analysis fees. When the merchandise requires scientific or technical laboratory analysis by SAT's Administración General de Aduanas—for example, textiles, apparel, footwear, pharmaceuticals, chemical products, fertilizers, or dietary supplements—the applicant must pay a fee of MXN 6,347 per sample analyzed (2026 rate under Article 52 of the Ley Federal de Derechos) using the D9 electronic payment form (Anexo 1 of the RGCE). The applicant may file the request without the payment receipt; if analysis is necessary, SAT will request the payment via official notice.

Timeline and deemed approval. SAT must resolve the ruling within three months from the date the file is deemed complete. Article 48 of the Ley Aduanera provides that the file is complete when SAT possesses the information and documentation that permit full identification of the merchandise and has carried out all necessary procedures, including obtaining technical opinions from the Consejo de Clasificación Arancelaria (Classification Council) if SAT elects to consult the Council. If SAT does not issue a ruling within three months of file completion, the fracción arancelaria proposed by the applicant is deemed correct by operation of law (affirmative fiction under Article 48, sixth paragraph, as it stood before the November 19, 2025 reform that repealed that paragraph—practitioners should verify current deemed-approval provisions with the reformed text).

Binding effect and validity. The ruling takes effect on the day following notification to the applicant and applies to all subsequent import or export operations of the same merchandise as described in the ruling. Article 48 provides that rulings remain valid as long as the facts, circumstances, and legal provisions that supported the ruling do not change. SAT may issue a single ruling covering multiple applicants when the merchandise description is identical. Rulings are published as non-binding classification criteria on the SAT portal to provide guidance to other traders.

Role of the Consejo de Clasificación Arancelaria. Article 48 authorizes SAT to seek technical opinions from the Consejo de Clasificación Arancelaria when resolving classification rulings. The Council is composed of SAT officials and expert panelists (peritos) proposed by confederations, chambers, industrial associations, and academic institutions. The Council's technical opinions—based on merchandise science (merceología) and tariff nomenclature—support SAT's final ruling. When SAT relies on a Council opinion to issue a ruling, the opinion must be published as a classification criterion within 30 days of the ruling's notification (Anexo 6 of the RGCE, Reglas de Operación del Consejo).

Source: Ley Aduanera, Arts. 47, 48 Source: Código Fiscal de la Federación, Arts. 18, 18-A, 19, 34 Source: Ley Federal de Derechos, Art. 52 Source: Anexo 2 de las RGCE 2026 – Trámites de Comercio Exterior Source: SAT portal – Consulta de clasificación arancelaria

Mexico's tariff schedule—the Tarifa de la Ley de los Impuestos Generales de Importación y de Exportación (TIGIE)—is organized as an eight-digit hierarchical classification system built on the World Customs Organization Harmonized System (HS). Classification at the eight-digit level determines both the applicable duty rate and the regulatory requirements for imports and exports. Understanding the TIGIE structure and rate types is essential for calculating landed cost, claiming preferential treatment, and filing entry declarations.

Eight-digit fracción arancelaria structure. Mexico, as a party to the International Convention on the Harmonized Commodity Description and Coding System (HS Convention), uses the first six digits of the HS nomenclature (chapters, headings, and subheadings maintained by the WCO) and adds two national-level digits (seventh and eighth) to create the fracción arancelaria (tariff item). The fracción arancelaria is the classification unit specified in the customs entry declaration (pedimento) and determines the duty rate. Article 1 of the LIGIE establishes that the tariff rates (cuotas) apply "atendiendo a la clasificación de la mercancía" (according to the classification of merchandise) at the fracción arancelaria level. The current LIGIE, enacted by decree on June 7, 2022, and in force since that date, implements the Seventh Amendment to the HS and maintains approximately 12,500 fracciones arancelarias.

NICO statistical codes (not legal classification). In addition to the eight-digit fracción arancelaria, the 2022 LIGIE introduced the Número de Identificación Comercial (NICO), a two-digit statistical suffix that brings the classification to ten digits. The NICO does not alter the duty rate or regulatory treatment; it serves solely for statistical reporting and commercial-intelligence purposes. Importers and exporters must report the NICO in the pedimento to enable more granular trade data, but the tariff rate and regulatory obligations are fixed at the eight-digit fracción arancelaria level. Regla Complementaria 10ª (Complementary Rule 10) of Article 2 of the LIGIE directs the Secretaría de Economía to publish correlation tables between fracciones arancelarias and NICOs. The NICO is a data-collection tool, not a legal classification determinant.

Three types of tariff rates. The TIGIE expresses tariff rates in three forms:

1. Ad valorem (ad valorem): A percentage applied to the customs value of the imported or exported merchandise, typically expressed as "X% ad valorem." Ad valorem rates are the most common form in the TIGIE. As of a 2018 Secretariat survey, approximately 12,417 fracciones arancelarias carried ad valorem rates; current figures may differ.

1. Specific (específico): A fixed monetary amount per unit of measure (e.g., USD per kilogram, USD per liter). Specific rates are rare in Mexico's tariff schedule. The 2018 survey counted only 15 fracciones arancelarias using specific rates. Specific rates are expressed in U.S. dollars (USD).

1. Mixed (mixto): A combination of ad valorem and specific duties applied simultaneously to the same merchandise. Mixed rates are uncommon; the 2018 survey identified 44 fracciones arancelarias employing mixed-rate structures.

In addition, certain fracciones arancelarias carry a zero rate (exento, labeled "Ex." or "0%"), and a small number of fracciones are designated as prohibited (prohibidas), which bar importation or exportation altogether.

MFN (general) rates vs. preferential rates. Article 1 of the LIGIE sets the most-favored-nation (MFN) or "general" duty rate for each fracción arancelaria—the rate applicable to goods of all origins unless a preferential trade agreement provides otherwise. Mexico has concluded more than a dozen free-trade agreements (FTAs), including the United States–Mexico–Canada Agreement (USMCA), the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), and FTAs with the European Union, the European Free Trade Association (EFTA), and numerous Latin American partners. Regla Complementaria 7ª (Complementary Rule 7) of Article 2 of the LIGIE provides that preferential tariff rates for FTA originating goods are included either in the fracción arancelaria itself or in a separate Apéndice annexed to the LIGIE. When a rate is included in the tariff proper, the fracción arancelaria displays the MFN rate in one column and preferential rates (labeled by country or agreement) in additional columns. When preferential rates are published in an Apéndice, the Apéndice specifies the fracción arancelaria, the agreement, the country or countries to which the preference applies, and the preferential rate or staging schedule. Importers claiming preferential treatment must meet the origin requirements of the relevant FTA and present the required certificate of origin or origin declaration at the time of entry.

Tariff-rate quotas (aranceles-cupo). Some fracciones arancelarias are subject to tariff-rate quotas (TRQs, known in Mexico as aranceles-cupo): a lower (often zero or reduced) in-quota duty rate applies to a specified annual volume, and a higher out-of-quota rate applies to imports exceeding that volume. TRQs are common for sensitive agricultural products and are administered by the Secretaría de Economía. The applicable TRQ allocations and procedures are published separately by decree.

Temporary tariff modifications. The Mexican government periodically issues presidential decrees under Article 131 of the Constitution to modify tariff rates on a temporary basis—for example, to protect domestic industry from unfair trade practices or dumping, or to address supply shortages. Recent decrees have established temporary increases (ranging from 5% to 50%) on hundreds of fracciones arancelarias in steel, aluminum, textiles, apparel, footwear, chemicals, and other sectors. These temporary modifications supersede the rates in Article 1 of the LIGIE for the decree's stated duration and apply unless an FTA preferential rate exempts the specific goods. Practitioners must verify that the fracción arancelaria they are applying reflects any in-force temporary modification published in the Diario Oficial de la Federación.

Accessing the TIGIE. The Secretaría de Economía maintains the official TIGIE database on the SNICE (Sistema Nacional de Información de Comercio Exterior) portal at www.snice.gob.mx, which provides real-time access to fracciones arancelarias, rates, NICOs, regulatory requirements (NOMs, permits), and historical trade statistics. Customs brokers and importers also use the SIAVI (Sistema de Información Arancelaria Vía Internet) portal at siavi.economia.gob.mx, which allows navigation by HS chapter, partida, subpartida, and fracción arancelaria and displays the applicable rates, non-tariff regulations, and commercial-trade data at the fracción and NICO levels.

Source: Ley de los Impuestos Generales de Importación y de Exportación, Arts. 1, 2 Regla Complementaria 7ª, Regla Complementaria 10ª Source: SNICE – LIGIE Information (Secretaría de Economía) Source: SIAVI – Preguntas Frecuentes Source: ACTUALIZACIÓN DE LA TARIFA (Secretaría de Economía, 2018)

Mexico's Reglas Generales (General Rules of Interpretation) govern the methodology for determining the correct eight-digit fracción arancelaria in the TIGIE. Article 2, Section I of the Ley de los Impuestos Generales de Importación y de Exportación (LIGIE) establishes six General Rules that mirror verbatim the General Rules for the Interpretation of the Harmonized System (GRI 1–6) maintained by the World Customs Organization. These rules apply hierarchically: GRI 1 controls, and each successive rule applies only if the merchandise cannot be classified under the preceding rules. Understanding the GRIs is essential to classification—a customs broker or importer who misapplies the GRIs risks incorrect duty calculations, regulatory penalties, and retroactive assessments.

GRI 1 — Heading text and Section / Chapter notes control. General Rule 1 provides that classification of merchandise is determined legally (legalmente) by the texts of the headings (partidas) and the Notes of Section or Chapter. GRI 1 also states that when merchandise prima facie can be classified in two or more headings, the conflict must be resolved by GRI 2 through GRI 5. In practice, GRI 1 resolves the majority of classification questions: a practitioner first reads the heading text and the relevant Section or Chapter notes to determine whether the merchandise falls within one heading's scope. Only if the merchandise could fit two or more headings (or none) does the practitioner proceed to GRI 2.

GRI 2 — Incomplete articles, unfinished articles, mixtures, and disassembled goods. GRI 2(a) addresses incomplete or unfinished merchandise: "Any reference in a heading to an article shall be taken to include a reference to that article incomplete or unfinished, provided that, as entered, the incomplete or unfinished article has the essential character (carácter esencial) of the complete or finished article. It shall also include a reference to that article complete or finished (or falling to be classified as complete or finished by virtue of this Rule), entered unassembled or disassembled (desmontado o sin montar)." This rule allows importers to classify disassembled or kit-form goods as the finished article—e.g., an automobile imported in knocked-down condition classifies as a complete automobile under the heading for automobiles—provided the unassembled parts exhibit the essential character of the finished product. GRI 2(b) covers mixtures and combinations of materials: "Any reference in a heading to a material or substance shall be taken to include a reference to mixtures or combinations of that material or substance with other materials or substances. Any reference to goods of a given material or substance shall be taken to include a reference to goods consisting wholly or partly of such material or substance. The classification of goods consisting of more than one material or substance shall be according to the principles of Rule 3." GRI 2(b) frequently leads to GRI 3 when a product contains multiple materials.

GRI 3 — Competing headings resolved by specificity, essential character, or numerical order. GRI 3 provides three sequential tests when merchandise prima facie classifies under two or more headings after applying GRI 1 and GRI 2:

• GRI 3(a) — Specific description prevails over general. The heading which provides the most specific description (descripción más específica) takes precedence over headings providing a more general description. For example, a heading for "electric toasters" is more specific than a heading for "electrothermal appliances" and therefore prevails.

• GRI 3(b) — Essential character. If GRI 3(a) does not resolve the classification, the merchandise is classified according to the material or component that imparts the essential character (confiera su carácter esencial) to the merchandise. Essential character is determined by examining the nature of the material, its bulk, quantity, weight, value, or the role the component plays in relation to the use of the article. GRI 3(b) is widely applied to composite goods (manufactures composed of different materials) and sets or kits of articles put up for retail sale. Determining essential character requires a fact-intensive analysis; SAT classification rulings and the Consejo de Clasificación Arancelaria's technical opinions frequently turn on the essential-character analysis.

• GRI 3(c) — Last in numerical order. When neither GRI 3(a) nor GRI 3(b) resolves the classification, the merchandise is classified in the heading that occurs last in numerical order (última partida por orden de numeración) among the headings under consideration. GRI 3(c) is a tie-breaker rule of last resort.

GRI 4 — Goods not elsewhere specified — classification by analogy. GRI 4 states that "goods which cannot be classified by reference to Rules 1, 2 or 3 shall be classified in the heading appropriate to the goods to which they are most akin (mayor analogía)." GRI 4 applies only when the merchandise genuinely does not fall within any existing heading. Practitioners rarely invoke GRI 4—when it applies, it requires classifying the merchandise by analogy to the heading covering the most similar goods.

GRI 5 — Packing materials and containers. GRI 5 has two parts:

• GRI 5(a) — Camera cases, musical-instrument cases, and similar containers. Containers specially shaped or fitted to contain a specific article or set of articles, suitable for long-term use, and entered with the articles for which they are intended, shall be classified with those articles when containers of that kind are normally sold with such articles. This rule does not apply when the container gives the whole its essential character (in that case GRI 3(b) applies).

• GRI 5(b) — Packing materials and containers for retail sale. Packing materials and containers entered with the goods they contain are classified with the goods if they are of a kind normally used for packing such goods. However, this provision is not binding when the packing materials or containers are suitable for repetitive use (susceptibles de ser utilizados razonablemente de manera repetida). In practice, single-use cardboard boxes or plastic film classify with the contents, while reusable crates or pallets classify separately.

GRI 6 — Subheading and fracción arancelaria classification. GRI 6 provides that the classification of merchandise in the subheadings of a heading is determined legally by the texts of those subheadings and any subheading notes, and mutatis mutandis by GRI 1 through GRI 5, with the critical limitation that only subheadings at the same level (mismo nivel) may be compared. Subheadings are structured hierarchically: first-level subheadings (one dash, sixth digit = 0 or a text without a numeric code) and second-level subheadings (two dashes, sixth digit ≠ 0). A practitioner applying GRI 6 first determines the correct first-level subheading, then (if the first-level subheading is subdivided) determines the correct second-level subheading. Regla Complementaria 1ª (Complementary Rule 1) confirms that GRI 1–6 apply equally to determine the correct fracción arancelaria within each subheading: the seventh and eighth digits are selected by applying the General Rules within the universe of fracciones arancelarias sharing the same six-digit subheading.

National Explanatory Notes are binding. Regla Complementaria 3ª directs the Secretaría de Economía and the Secretaría de Hacienda y Crédito Público to publish Notas Explicativas de la Tarifa arancelaria (Tariff Explanatory Notes) by joint agreement in the Diario Oficial de la Federación. These Explanatory Notes—which incorporate both the WCO Harmonized System Explanatory Notes and Mexico's national notes (Notas Nacionales)—are mandatory (de aplicación obligatoria) for determining the applicable heading and subheading. Unlike the advisory status of HS Explanatory Notes in some jurisdictions, Mexico's Regla Complementaria 3ª gives the Explanatory Notes the force of law. Practitioners must consult the published Notas Explicativas when applying the GRIs; a classification that contradicts a published Explanatory Note is incorrect as a matter of law.

Hierarchy of authority. The GRIs operate hierarchically. A practitioner starts with GRI 1 (heading text and notes); if GRI 1 does not resolve the classification uniquely, the practitioner applies GRI 2 (incomplete/unfinished/disassembled articles; mixtures); if still unresolved, GRI 3 (specific description, essential character, last in numerical order); and so on. The GRIs are applied sequentially, not simultaneously. Once a rule provides the answer, the analysis stops. A classification decision that jumps directly to essential character (GRI 3(b)) without first confirming that the merchandise could classify under two or more headings after GRI 1 and GRI 2 is methodologically flawed and vulnerable to challenge on audit or in a classification ruling dispute.

Source: Ley de los Impuestos Generales de Importación y de Exportación, Art. 2, Sección I — Reglas Generales; Sección II, Regla Complementaria 1ª, Regla Complementaria 3ª

Incorrect tariff classification carries significant legal and financial consequences in Mexico. The Ley Aduanera establishes a regime of administrative penalties, retroactive duty assessments, interest charges, and potential suspension or revocation of customs-broker authorizations. Both the importer and the customs broker (or customs agency) face liability for classification errors, and SAT can pursue collection actions, embargo merchandise, and initiate administrative or even criminal proceedings for fraudulent misclassification.

Customs broker and agency responsibility for correct classification — Article 54. Article 54 of the Ley Aduanera imposes strict professional liability on customs brokers (agentes aduanales) and customs agencies (agencias aduanales). The broker or agency is responsible (serán responsables) for the veracidad y exactitud (truthfulness and accuracy) of the data and information supplied in the customs entry declaration (pedimento), for the correct determination of contributions payable, for the determination of the proper customs regime, and specifically for the correct tariff classification (correcta clasificación arancelaria) and the exact determination of the NICO (commercial identification number). The broker or agency must also ensure that the importer or exporter possesses the documents that prove compliance with obligations in foreign-trade matters and with non-tariff regulations and restrictions. This responsibility extends to all information in the pedimento that the broker files on behalf of the client. If a classification error is discovered — whether during recognition inspection (reconocimiento aduanero), verification of goods in transport, or later audit — Article 54 liability attaches to the broker or agency as well as to the importer.

Customs brokers are personally liable for classification errors committed by their employees and mandatarios. Under Article 160, sixth paragraph, of the Ley Aduanera, a customs broker is ilimitadamente responsable (unlimitedly liable) for the acts of his employees or authorized assistants (empleados o dependientes autorizados) and his mandatarios (mandated representatives). A classification error made by an employee acting within the scope of employment is attributed to the broker. This unlimited personal liability is a distinguishing feature of the Mexican customs-broker profession.

Types of penalties: fines, retroactive duties, interest, and embargo. The Ley Aduanera's sanctions regime is organized by type of infraction. Misclassification can give rise to multiple overlapping penalties depending on the nature and effect of the error:

• Article 178 — general penalty for incorrect classification or value. Article 178 addresses infractions that result in non-payment or underpayment of import or export duties. When the misclassification causes an omission of payment (omisión en el pago) of customs duties, VAT, or other contributions, the infractor (importer and/or customs broker) is subject to a fine equal to the omitted amount, with a floor and ceiling established by law. The fine can range from the amount equal to the contributions omitted to multiples thereof, depending on whether the infractor self-corrects or is discovered on audit. In addition to the fine, the importer must pay the retroactive duty assessment (the contributions that should have been paid), plus recargos (surcharges, which are interest-like charges calculated under Article 21 of the Código Fiscal de la Federación).

• Article 184 — penalties on customs brokers and agencies for incorrect data in the pedimento. Article 184 establishes specific penalties for customs brokers and agencies when the pedimento contains incorrect information. Although the current text of Article 184 does not call out classification errors as a stand-alone infraction, SAT has historically applied Article 184, fractions III and IV, when a broker files a pedimento with an incorrect fracción arancelaria that results in underpayment of duties. The penalties under Article 184 can include monetary fines and, for repeat or egregious violations, suspension (suspensión) of the broker's authorization to operate (under Article 165) or revocation (revocación) of the broker's patent (under Article 164). Suspension typically lasts between one and three months for first offenses; revocation is permanent.

• Embargo precautorio (precautionary seizure). Article 151 of the Ley Aduanera authorizes SAT to impose an embargo precautorio — a precautionary seizure of the merchandise — when a classification infraction is detected during recognition inspection or verification of goods in transport. The merchandise remains under customs custody until the importer posts a bond or pays the omitted duties. Embargo precautorio is common when SAT suspects that the declared classification is incorrect and that the true classification would result in substantially higher duties or would trigger a prohibited-import or restricted-merchandise rule. The merchandise cannot be released until the importer pays the duties or posts a guarantee (bond or cash deposit) equal to the amount SAT calculates as the correct duty, plus penalties.

Interest and surcharges — Article 21 of the Código Fiscal de la Federación. When misclassification results in late payment of duties, the importer must pay recargos (late-payment surcharges) under Article 21 of the Código Fiscal de la Federación, calculated at a monthly rate tied to the TIIE (Tasa de Interés Interbancaria de Equilibrio) plus a statutory margin. The recargos accrue from the original due date of the duty until the date of payment or resolution of the administrative proceeding. The monthly recargo rate is set by SAT and updated regularly; practitioners must verify the current published rate. Recargos can accumulate to substantial amounts during multi-year audits.

Cancellation of preferential-tariff treatment. A related consequence of misclassification arises in the preferential-origin context. If an importer claims a preferential tariff rate under a free-trade agreement (e.g., USMCA, CPTPP, or an EU FTA) and SAT subsequently determines that the classification was incorrect, SAT can retroactively cancel the preferential-tariff treatment and assess the general (MFN) duty rate plus penalties. Misclassification that invalidates a certificate of origin can also result in penalties on the broker who validated the certificate under Article 54.

Criminal liability for fraudulent misclassification. Article 105 of the Código Fiscal de la Federación establishes criminal penalties for smuggling (contrabando), including the deliberate misclassification of merchandise to evade duties or to import prohibited goods. When a misclassification is deemed fraudulent — for example, classifying firearms as sporting goods or classifying restricted pharmaceuticals as food supplements — SAT can refer the case to the Ministerio Público (public prosecutor) for criminal prosecution. Conviction can result in imprisonment of three months to nine years, depending on the value of the evaded duties, plus permanent revocation of the broker's authorization. Criminal liability requires proof of intent (dolo), not mere negligence.

Mitigating factors: spontaneous correction and binding rulings. The Ley Aduanera and the Código Fiscal de la Federación provide limited mitigation for voluntary self-correction. If an importer discovers a classification error before SAT opens an audit or issues an inspection notice and files a corrective pedimento (pedimento complementario) paying the omitted duties plus recargos, the monetary penalties under Article 178 are reduced or waived under Article 73, first paragraph, of the Código Fiscal de la Federación. However, the reduced penalty is available only if the self-correction is truly spontaneous — filed before SAT takes any enforcement action. In addition, importers who obtain a binding advance classification ruling (consulta sobre clasificación arancelaria) under Articles 47–48 of the Ley Aduanera can rely on that ruling as a defense against penalties if SAT later takes a contrary position on the same merchandise, provided the facts and legal provisions have not changed since the ruling was issued.

Updated penalties and monetary amounts. Article 5 of the Ley Aduanera directs that the monetary amounts of fines and other charges stated in the law be updated annually in accordance with Article 70 of the Código Fiscal de la Federación (inflation adjustment). SAT publishes the updated penalty amounts each calendar year in the Reglas Generales de Comercio Exterior. The most recent updates (2026 rates) are published in the Reglas Generales de Comercio Exterior para 2026. Practitioners must verify the applicable updated amounts when calculating exposure.

Practical consequences: audit exposure and compliance programs. In practice, classification errors discovered on audit are the leading cause of retroactive duty assessments in Mexico. SAT conducts post-entry audits (auditorías) under Article 42 and Article 144 of the Ley Aduanera, with a lookback period of five years from the date of entry under the general statute of limitations in Article 67 of the Código Fiscal de la Federación. A single incorrect classification repeated across hundreds of entries over multiple years can generate millions of pesos in retroactive duties, interest, and fines. Many importers implement internal classification-review and post-entry-audit programs to identify and self-correct classification errors before SAT discovers them.

Source: Ley Aduanera, Arts. 54, 151, 160, 164, 165, 178, 184 Source: Código Fiscal de la Federación, Arts. 21, 67, 70, 73, 105

Section Notes and Chapter Notes are legally binding components of the TIGIE and control classification decisions alongside the heading texts. General Rule of Interpretation 1 (GRI 1) establishes that classification is determined legally by the texts of the headings and the Section or Chapter Notes. A classification decision that ignores a relevant note is incorrect as a matter of law, even if the merchandise appears to fit within a heading's text. Understanding how to locate, read, and apply the Notes is essential for every customs broker and importer classifying merchandise in Mexico.

Legal status and binding effect. Article 2, Section I of the LIGIE incorporates verbatim the six General Rules for the Interpretation of the Harmonized System (GRI 1–6) maintained by the World Customs Organization (WCO). The first sentence of GRI 1 provides: "The classification of goods is determined legally (legalmente) by the texts of the headings (partidas) and by the Section or Chapter Notes (por los textos de las partidas y de las Notas de Sección o de Capítulo)." This sentence establishes a hierarchy: the Notes stand on the same legal footing as the heading texts themselves. The International Convention on the Harmonized Commodity Description and Coding System (HS Convention), to which Mexico is a Contracting Party, defines the "Harmonized Commodity Description and Coding System" as comprising "the Nomenclature … the Section, Chapter and Subheading Notes and the General Rules for the interpretation of the Harmonized System." WCO guidance confirms that Notes "are legally binding and provide definitions of terms, exclusions and inclusions in relation to scope or directions in relation to the classification of goods."

Structure of the Notes in the TIGIE. The LIGIE organizes the tariff into 21 Sections (Sección I through Sección XXI) subdivided into 97 Chapters (Capítulo 1 through Capítulo 97). Each Section and many Chapters begin with one or more Notas (Notes) that govern the scope, interpretation, and application of the headings and subheadings within that Section or Chapter. Section Notes appear immediately after the Section title and before the first Chapter of the Section; Chapter Notes appear immediately after the Chapter title and before the first heading (four-digit partida) of the Chapter. For example, Section I (Animales Vivos y Productos del Reino Animal) opens with two Section Notes that apply to all five chapters (Chapters 1–5) within Section I. Chapter 4 (Leche y Productos Lácteos) contains its own set of Chapter Notes that apply only to the headings within Chapter 4. A practitioner classifying dairy products must read both the Section I Notes and the Chapter 4 Notes before selecting a heading.

Types of content in Section and Chapter Notes. The Notes serve multiple functions:

• Definitions. Many Notes define terms used in the headings or subheadings. For example, Note 1 to Chapter 50 defines "silk yarn" for purposes of that Chapter, and Note 2 to Chapter 71 defines "platinum" as including platinum, iridium, osmium, palladium, rhodium, and ruthenium. These definitions control the scope of the affected headings and may differ from common usage or from definitions in other Chapters.

• Exclusions. Notes often exclude specific goods from a Section or Chapter and direct the classifier to the correct heading elsewhere. For example, Note 1(a) to Section VI (Productos de las Industrias Químicas o de las Industrias Conexas) excludes certain organic chemical products and redirects them to Chapters 28 or 29. A good that falls within the literal text of a Chapter 38 heading but is excluded by a Section VI Note cannot be classified in Chapter 38.

• Inclusions and clarifications. Notes may specify that certain goods are included in a heading or Section even when the heading text alone might be ambiguous. Note 3 to Chapter 61 (Prendas y Complementos de Vestir, de Punto) clarifies that "prendas de vestir" includes articles for babies, even though babies are not explicitly mentioned in the heading texts.

• Scope limitations. Some Notes limit the application of a heading to goods meeting specific technical criteria. Note 4 to Chapter 84 (Reactores Nucleares, Calderas, Máquinas, Aparatos y Artefactos Mecánicos; Partes de estas Máquinas o Aparatos), for example, establishes the conditions under which an incomplete machine may be classified as if it were complete.

• Classification directions. Notes may direct the classifier to apply a specific methodology or to prefer one heading over another in cases of potential overlap. Note 2 to Section XI (Materias Textiles y sus Manufacturas) states that goods classifiable in Chapters 50–55 on the one hand, or Chapters 56–59 on the other, are classified in Chapters 50–55 if the textile component gives the goods their essential character.

Hierarchy: Section Notes vs. Chapter Notes vs. heading texts. When a conflict appears to exist between a Section Note and a Chapter Note, the more specific provision controls. Chapter Notes apply only to the headings within that Chapter, so a Chapter Note that addresses a narrow category of goods prevails over a broader Section Note covering the same goods, unless the Section Note expressly states otherwise. The Notes, whether at Section or Chapter level, always prevail over the heading texts when the two conflict. GRI 1 is explicit: classification is determined by the heading texts and the Notes "provided such headings or Notes do not otherwise require." In other words, if a Note says goods are excluded, the heading cannot override the exclusion.

Subheading Notes. In addition to Section and Chapter Notes, certain Chapters contain Subheading Notes (Notas de Subpartida) that apply only when classifying at the six-digit subheading level within a heading already selected. Subheading Notes are governed by GRI 6, which provides that classification in the subheadings of a heading is determined by the texts of those subheadings and any Subheading Notes, applying GRI 1–5 mutatis mutandis. A Subheading Note does not alter the scope of the heading as a whole; it operates only to direct classification among competing subheadings within that heading. For example, Subheading Note 1 to Chapter 71 defines "platinum" for purposes of distinguishing platinum jewelry (subheading 7113.11) from other precious-metal jewelry, but that definition does not change the scope of heading 71.13 itself.

How to locate and read the Notes. The official LIGIE text published by the Cámara de Diputados (available at diputados.gob.mx) displays the Notes in the same order as the WCO Harmonized System: Section Notes appear at the start of each Section, Chapter Notes at the start of each Chapter, and Subheading Notes (when they exist) immediately before the first subheading of the relevant heading. Practitioners using the Secretaría de Economía's SNICE or SIAVI portals will find the Notes embedded in the tariff database; SIAVI displays the applicable Notes when navigating to a specific Chapter or heading. When classifying merchandise, best practice is to:

1. Identify the likely Section and Chapter based on the nature of the goods.
2. Read the Section Notes for that Section in full.
3. Read the Chapter Notes for the relevant Chapter in full.
4. Apply GRI 1 using the heading texts together with the Notes.
5. If classification reaches the subheading level, check for Subheading Notes and apply them under GRI 6.

National Explanatory Notes (Notas Nacionales) supplement the Notes but are subordinate. Regla Complementaria 3ª of Article 2 of the LIGIE directs the Secretaría de Economía and the Secretaría de Hacienda y Crédito Público to publish Notas Explicativas de la Tarifa arancelaria (Tariff Explanatory Notes) in the Diario Oficial de la Federación. These Explanatory Notes incorporate both the WCO Harmonized System Explanatory Notes and Mexico's national explanatory notes (Notas Nacionales). Regla Complementaria 3ª gives the Explanatory Notes mandatory (de aplicación obligatoria) status for determining the applicable heading and subheading. However, the Explanatory Notes do not override the Section or Chapter Notes themselves; they interpret and clarify the Notes and headings. When a conflict exists between an Explanatory Note and a Section or Chapter Note, the Section or Chapter Note (which is part of the legal text of the LIGIE under GRI 1) controls.

Common practitioner errors. The most frequent classification mistakes involve failing to consult the Notes:

• Classifying by heading text alone without reading the Section or Chapter Notes. A heading may appear to cover the goods, but a Note may exclude them or redirect them to another Chapter.
• Assuming the heading text is exhaustive. Many headings use the phrase "los demás" (other) or contain general descriptions; the Notes often supply the precise boundaries.
• Relying on national-level fracción arancelaria descriptions without verifying the Notes. The seventh- and eighth-digit national subdivisions are subordinate to the six-digit HS subheadings; a national fracción arancelaria cannot override a Chapter Note exclusion.
• Ignoring Section Notes when the goods appear to fit a Chapter heading. Section Notes apply to every Chapter within the Section. An exclusion in the Section Note affects all headings in all Chapters of that Section.

Consequences of ignoring the Notes on audit. When SAT conducts a verification (verificación) or post-entry audit and determines that the classification is incorrect because the importer failed to apply a Section or Chapter Note, the importer and the customs broker face liability under Articles 54 and 178 of the Ley Aduanera: retroactive duty assessments, interest charges (recargos), and monetary penalties. Because GRI 1 gives the Notes the same legal weight as the heading texts, a classification that contradicts a Note is a classification error, not a matter of interpretive discretion.

Advance rulings and the Notes. When requesting a binding advance classification ruling under Articles 47–48 of the Ley Aduanera, the applicant must identify the proposed classification and explain the legal reasoning supporting that classification. Best practice is to cite the relevant Section or Chapter Notes in the ruling request, demonstrating that the proposed classification complies with the Notes. SAT's classification ruling will likewise cite the Notes when they are determinative. A ruling issued without reference to an applicable Note may be vulnerable to challenge or revision if the Note was overlooked.

Source: Ley de los Impuestos Generales de Importación y de Exportación, Art. 2, Sección I — Reglas Generales; Sección II, Regla Complementaria 3ª Source: International Convention on the Harmonized Commodity Description and Coding System, Art. 1 definitions, Art. 3 obligations of Contracting Parties Source: WCO Guidance on HS Change Proposals — Legal Notes Source: Ley Aduanera, Arts. 47, 48, 54, 178