Mexico Rewrote the Rulebook Around Your NOMs. It Is Already in Force.

What changed, and from when

On Friday 4 September 2026 the Diario Oficial de la Federación published the DECRETO por el que se expide el Reglamento de la Ley de Infraestructura de la Calidad, signed on 28 August 2026. Two hundred fifty three articles, four Libros, eleven transitory provisions.

The first transitory provision is one sentence:

"El presente Reglamento entra en vigor el día hábil siguiente al de su publicación en el Diario Oficial de la Federación."

It enters into force the business day following publication. Publication was Friday; the following business day was Monday 7 September 2026.

So this is not a warning about something coming. It is already law, and it has been since 7 September.

The Ley de Infraestructura de la Calidad itself is not new. What is new is that it finally has implementing regulations of its own. Until that day, the regulation actually being applied on the ground was the one written for the law that the Ley de Infraestructura de la Calidad replaced.

What ended on 7 September

Transitory provision Segundo:

"Con la entrada en vigor del presente Reglamento, se abroga al Reglamento de la Ley Federal sobre Metrología y Normalización, publicado en el Diario Oficial de la Federación el 14 de enero de 1999, y sus reformas, así como todas las disposiciones que se opongan a lo dispuesto en este Reglamento."

A regulation from January 1999 was repealed. Twenty seven years of accumulated practice, procedure, forms and habit built on top of it.

Transitory provision Cuarto:

"Con la entrada en vigor del presente Reglamento, se cancelan los anteproyectos y proyectos de Normas Mexicanas que se encuentren en trámite."

Every draft and every project for a Norma Mexicana that was in process was cancelled. No grace period, no transition, no mechanism to convert the work already done. If your industry association had a Norma Mexicana in the pipeline, it stopped on 7 September.

The Normas Mexicanas already published are treated differently. Under transitory provision Quinto they remain in force until the Secretaría publishes a cancellation declaration, or until a Estándar in force covers the same subject matter. Transitory provision Sexto then sets the clock: once the Comités Técnicos de Estandarización are installed, the bodies empowered to standardise have treinta y seis meses improrrogables, thirty six non extendable months, to issue Estándares where Normas Mexicanas exist. Where they fail to, the Secretaría publishes the cancellation declaration for those Normas Mexicanas.

There is one carve out worth knowing if your product specification cross references a Norma Mexicana. When a Estándar begins to apply to the same subject matter, the Organismos Nacionales de Normalización must request cancellation of the Norma Mexicana the following day. But Normas Mexicanas referenced inside a Norma Oficial Mexicana stay in force until the Norma Oficial Mexicana itself is amended. If your compliance file leans on a Norma Mexicana because a NOM points to it, that reference does not evaporate.

Your documents survive, and here are the two conditions

This is the provision that gets read, and it reads like good news.

Transitory provision Séptimo:

"Los documentos de Evaluación de la Conformidad emitidos con anterioridad a la entrada en vigor de este Reglamento por los Organismos de Evaluación de la Conformidad y las Autoridades Normalizadoras, continuarán vigentes en sus términos en todo lo que no se oponga a la Ley y al presente Reglamento, hasta en tanto se expidan los que los sustituyan."

Conformity assessment documents issued before 7 September continue in force on their own terms. Certificates, test reports, inspection reports, dictámenes.

Read the two conditions attached to the survival.

"En todo lo que no se oponga a la Ley y al presente Reglamento." In everything that does not conflict with the Law and this Reglamento. The document survives to the extent of its consistency with a text that was published on 4 September. Nobody has yet catalogued which existing documents contain something that conflicts, and the provision does not create a procedure for finding out. The conflict is determined when someone raises it.

"Hasta en tanto se expidan los que los sustituyan." Until the replacing documents are issued. The survival is expressly interim.

Neither condition is a defect in the drafting. Both are ordinary transitional technique. The problem is that the sentence is quotable without them, and the quotable half is the reassuring half.

The three year clock, and it is not yours

Now read the provision that follows it, because these two are consecutive and they are usually read apart.

Transitory provision Octavo:

"Las autorizaciones, acreditaciones y aprobaciones emitidas con anterioridad a la entrada en vigor de este Reglamento cuentan con un periodo de tres años para renovarse, conforme a las disposiciones contenidas en la Ley y el presente Reglamento. En caso de no atender lo dispuesto en este transitorio, se entienden como cancelados."

Authorisations, accreditations and approvals issued before 7 September have three years to be renewed under the new Law and this Reglamento. And then the sentence that matters: failing to comply, they are understood as cancelled. Not subject to cancellation, not liable to be revoked after a hearing. Understood as cancelled.

Put the two provisions side by side.

The Séptimo is about your documents. The Octavo is about the entity that issued them: the certification body, the testing laboratory, the inspection unit, and the approval or accreditation that lets it act at all.

This is the asymmetry, and it is the reason this piece exists. The plant reads the Séptimo and relaxes, because the Séptimo speaks about the thing sitting in the compliance binder. The exposure lives in the Octavo, and it belongs to somebody else. Your certificate is only as good as the accreditation of the body whose letterhead it carries, and that accreditation is now on a three year clock that your organisation cannot see, cannot manage and will not be told about.

A practical consequence follows immediately. The renewal status of your conformity assessment bodies is now a supplier management question, not a paperwork question. It belongs in the same conversation as a critical supplier's financial condition, because the failure mode is the same: the counterparty stops being able to perform and you find out late.

And a certifier on its way out contaminates results before it loses anything

There is a second article that closes the pincer, and it operates well before the three years run.

Article 111 deals with conformity assessment results obtained by a body that subcontracted other bodies. Its opening line is not permissive:

"Los resultados de la Evaluación de la Conformidad obtenidos por los Organismos de Evaluación de la Conformidad que subcontrató a otros organismos deben ser rechazados cuando incurran en los supuestos previstos en los artículos 58, fracciones I, VI, VII y VIII, o 59, fracción IX, de la Ley, así como en los supuestos siguientes:"

Results must be rejected. Two of the five listed situations should change how your plant contracts for certification.

"III. Se omita informar a quienes les soliciten la Evaluación de la Conformidad, de la subcontratación de los servicios o el alcance de la subcontratación"

"IV. Se encuentre en proceso de suspensión total o parcial, o de cancelación, la acreditación o Aprobación de cualquiera de los Organismos de Evaluación de la Conformidad involucrados"

Fraction III gives you something to use. If the body that certified your product subcontracted part of the work and did not tell you, or did not tell you the scope of what it subcontracted, the results must be rejected. That converts a question you may never have asked into a right you can exercise: ask, in writing, whether any part of the assessment was subcontracted and to whom. The answer, or the absence of one, is now legally consequential.

Fraction IV is the one that shortens the three year horizon. A body does not have to lose its accreditation to spoil your file. It is enough that any of the involved bodies is in the process of total or partial suspension, or of cancellation. So the risk window opens when the proceeding opens, not when it ends. And the plant is not a party to that proceeding.

The other three grounds are worth a line each: failure to put the subcontracting in writing between the bodies, conflict of interest in the provision of the services or in the confidentiality provisions, and contravention of the Ley Federal del Trabajo, the Law, this Reglamento or any other applicable provision.

One counterweight, because it cuts the other way and it is easy to miss. Article 106 provides that the cancellation of an Entidad de Acreditación does not affect the accreditations it has already issued to conformity assessment bodies. The chain does not collapse from the top.

Self declaration is not a saving. It is a transfer.

The Reglamento contains a mechanism that will be presented to your plant as a cost reduction, and it is worth understanding before somebody adopts it.

Article 113:

"se entiende por autodeclaración en la Evaluación de la Conformidad, la manifestación voluntaria y de buena fe que realizan los sujetos obligados respecto del cumplimiento de una Norma Oficial Mexicana o Estándar, sin la necesidad de acudir a un Organismo de Evaluación de la Conformidad. La autodeclaración no aplica para instrumentos sujetos a Control Metrológico Legal."

A voluntary, good faith statement of compliance, without going to a conformity assessment body. Not available for instruments subject to legal metrological control.

Four things bound it, and each one belongs to somebody other than you.

You do not decide whether it is available. Article 112 states that risk categorisation belongs "de manera exclusiva", exclusively, to the Autoridades Normalizadoras, and that risk is classified as high, moderate or low. Article 114 makes self declaration applicable only where compliance is considered low risk by that authority and its Procedimiento de Evaluación de la Conformidad so provides.

You assume everything on issuing it. Article 115, final paragraph:

"Al expedir el documento que exprese la autodeclaración en la Evaluación de la Conformidad, el productor, fabricante, proveedor, comercializador, productor, importador o según corresponda, asume plena responsabilidad del cumplimiento del bien, producto, proceso o servicio."

Full responsibility for compliance of the good, product, process or service. The word is plena. Whatever residual comfort came from a third party's signature on a certificate is what you are giving up in exchange for the saving.

The door can close without you doing anything. Article 116 lists when self declaration may cease, and fraction II is the one to watch: when the Autoridad Normalizadora modifies the risk classification. A reclassification you do not participate in can remove the mechanism from under a product line that has been self declaring for years.

It has a form, and the form has a named signatory. Article 117 requires, as a minimum, the issuer's full name, telephone and contact address; identification and description of the goods, products, processes or services; the declaration of conformity; identification of the Normas Oficiales Mexicanas complied with; the date and place of issue; and:

"VI. La firma, el nombre completo y el cargo de la función de la o las personas autorizadas para actuar en nombre del emisor."

A signature, a full name and a position. Article 115 fraction II and fraction III then require the supporting documentation to be produced and maintained for the authority's market surveillance, including first party laboratory results where the product's physicochemical characteristics are the obligated party's responsibility.

Our reading, and it is a reading rather than a quotation: self declaration is appropriate where the plant already holds the technical file it would have had to hand a certifier anyway. Where the file does not exist, self declaration does not save the cost of building it. It moves the consequence of not having built it onto a named individual at your company.

The authorisation almost nobody asks for

Here is a mechanism that sits in the Reglamento and matches a situation foreign operators run into constantly, which is that the plant runs the parent company's technology and the Norma Oficial Mexicana names a different one.

Article 108 lets interested parties apply for authorisation to use or apply alternative materials, equipment, processes, test methods, mechanisms, procedures or technologies foreseen in the corresponding Norma Oficial Mexicana. The application goes to the Autoridad Normalizadora that issued the NOM, with proof of the address where they will be used, a report of the activity, a description of the elements, the personnel responsible, a comparative table of test results against those foreseen in the NOM, a description of the methodology, and the original payment receipt under the Ley Federal de Derechos.

Article 109 gives the procedure a shape worth knowing before you decide it is not worth the trouble. The authority must resolve within forty five days. Within five days it sends a copy to the competent national standardisation consultative committee, and note what it must do first:

"para lo cual debe testar la información que identifique a la persona solicitante"

It must redact the information identifying the applicant. Your identity does not travel to the committee with the file.

The clock is suspended from the notification of an information request or an inspection order, and resumes the business day after you deliver or the visit concludes. The committee has ten days to opine, and:

"VI. Si el comité consultivo nacional de normalización no emite su opinión en el plazo previsto para tal efecto, se entiende que no tiene observaciones"

Silence from the committee is treated as no objection. The authority may double the term, on notice.

One trap, and it is the same one that catches foreign groups in their corporate filings. The final paragraph of article 108:

"Toda información y documentación que se encuentre en un idioma distinto al español debe presentarse en original y su correspondiente traducción a este idioma realizada por un perito que cuente con cédula profesional para ejercer la profesión de traductor."

Original plus a translation by an expert holding a professional licence as a translator. Your parent company's engineering documentation, in the language it was written in, does not go in as it stands. Budget the translation into the timeline, not after it.

The border is not where this gets decided

Two points here, and they point in opposite directions.

The customs mechanism is a faculty, not an obligation. Article 110:

"las Autoridades Normalizadoras pueden emitir las alternativas que permitan a los importadores demostrar el cumplimiento de las Normas Oficiales Mexicanas en el punto de entrada al país, siempre que se protejan los Objetivos Legítimos de Interés Público y se garantice la seguridad de los bienes, productos, procesos y servicios a importarse."

The verb is pueden. They may. And the path is not short: the proposal goes to the relevant Comité Consultivo Nacional de Normalización for its opinion, and only after a favourable opinion from the Comisión does the authority request publication in the PLATIICA, within ten days of issue. As at the date of this guide we are not aware of any alternative issued and published under this article. Until one is, the article is a power in reserve rather than a procedure you can use.

Meanwhile, the surveillance happens where you make the product. Article 224, second paragraph, is explicit about where verification and vigilance may be practised:

"en los lugares donde se elabore un bien o producto, o una parte del mismo, se realice algún proceso o una fase del mismo, administren, almacenen, transporten, distribuyan o expendan bienes o productos o en los que se presenten servicios, incluyendo aquellos en tránsito."

Where a good is made, or a part of it. Where a process is carried out, or a phase of it. Storage, transport, distribution, points of sale, and goods in transit. That is the plant, the warehouse and the truck, not only the customs booth.

Article 225 adds that these procedures are commenced de oficio, en cualquier momento, on the authority's own initiative at any time, and on a complaint where there are elements presuming non compliance. Article 227 sets out what a complaint must contain, including the name or corporate name and domicile of the party complained of, which tells you plainly that a competitor or a customer can start this. Article 226 requires the auxiliary subjects of the authorities to forward information they detect suggesting non compliance.

Who those auxiliary subjects are is stated in the Law, not in the Reglamento. Article 6, second and third paragraphs:

"Son auxiliares de las autoridades federales, las estatales y municipales en los ámbitos de sus respectivas competencias, para lo cual, colaborarán y otorgarán las facilidades necesarias en la aplicación y observancia de la presente Ley, en términos de los convenios de colaboración que suscriban con la Secretaría y las Autoridades Normalizadoras para esos efectos."

"De igual forma, las Entidades de Acreditación y los Organismos de Evaluación de la Conformidad deberán auxiliar a la Secretaría y a las Autoridades Normalizadoras, en las actividades previstas en esta Ley, cuando les sea requerido."

Two layers. The first is state and municipal authorities, which cooperate under collaboration agreements. The second is the one that changes a plant's calculation: accreditation entities and conformity assessment bodies, that is, the body that certified your product and the entity that accredited it, must assist the authority in the activities foreseen in the Law. Your certifier is not only your supplier. By statute, it is an auxiliary of the authority that supervises you.

One precision, and it is a reading rather than a quotation. The Law conditions that assistance on its being "requerido", requested; article 226 of the Reglamento speaks of forwarding information that auxiliary subjects detect and that suggests non compliance. How the two texts fit together, whether the body's duty arises only on request or also on its own initiative, is a question the drafting leaves open and we do not settle here. What is not open is that what your certifier knows about your product can reach the authority by a route that does not pass through you.

Article 233 lists the vigilance acts as visits, requests for information and documentation, and interviews, in person or remote. Article 234 lists the verification acts as visits, requests for information and documentation, laboratory testing, sample verification and ocular inspection.

And article 237 describes what happens when it goes badly. The authority must immediately issue an administrative act prohibiting commercialisation and immobilising the goods until they are reconditioned, reprocessed, repaired or substituted, notified to the party responsible for the product and where applicable to the distributors. If they cannot be reconditioned, reprocessed, repaired or substituted within the term set, the necessary steps are taken to order their recovery, withdrawal from the market or destruction.

Revision note: this section was updated on 7 September 2026 to incorporate article 6 of the Ley de Infraestructura de la Calidad. The version published earlier that day referred to auxiliary subjects without defining them.

The narrow door, and it is narrower than people assume

There is one relief valve, and it is worth reading precisely because it is routinely stretched to cover things it does not cover.

Article 239 defines inexactitud de datos, inaccuracy of data, as the error in the information and specifications established in the applicable Norma Oficial Mexicana, provided that no mandatory information, data or legends are omitted, nothing prohibited is displayed, and the consumer is not led into error, confusion or deception. On that condition it applies to three cases:

"I. Errores ortográficos en la expresión de unidades de medida del Sistema General de Unidades de Medida, así como en la redacción; II. Tamaño de letra y tipografía diferente a la requerida por la Norma Oficial Mexicana, o III. Cambio de denominación, razón social, domicilio o datos fiscales del responsable del producto."

And then:

"Las autoridades competentes de forma coordinada con la Secretaría, pueden conceder un plazo de hasta veinticuatro meses a efecto de corregir la inexactitud."

Up to twenty four months to correct.

Two conclusions, one of which is more useful than it looks.

A spelling error in a unit of measure and a missing mandatory legend are not the same problem. The first is a correctable inaccuracy with up to two years of runway. The second is outside article 239 by its own opening condition, and lands in the immobilisation logic of article 237. Any internal escalation matrix for labelling findings should distinguish the two, because right now most of them do not.

Fraction III should be read by anyone restructuring a Mexican entity. A change of the responsible party's corporate name, legal name, domicile or tax data is classified as a correctable inaccuracy, with up to twenty four months to correct. A merger, a name change or a change of registered office does not invalidate your existing labelling. It opens a correction window. That is a materially better position than the one clients usually assume they are in, and it is the kind of thing worth confirming before a reorganisation is timed around a labelling reprint.

Where "intentional" comes from, and why knowing is worse than not knowing

The last provision is the one to take to the operations meeting.

Article 242 explains how the aggravating factors of article 157 of the Law are established. Fraction I:

"El carácter intencional de la acción u omisión constitutiva de la infracción se acredita cuando la persona infractora importe, produzca, fabrique o comercialice productos, realice procesos o preste servicios, con conocimiento de las consecuencias patrimoniales o jurídicas derivadas del incumplimiento de las obligaciones contraídas o de las disposiciones de la Ley, este Reglamento, las Normas Oficiales Mexicanas y demás disposiciones jurídicas aplicables."

The intentional character of the act or omission is established when the infringing party operates with knowledge of the patrimonial or legal consequences of the non compliance.

Sit with that alongside everything above.

An internal audit that identifies a NOM gap and is not remediated is knowledge. An email from a certification body announcing that its accreditation is in a suspension proceeding is knowledge. A compliance calendar noting that a laboratory's accreditation expires within the three year window is knowledge. In each case the document that proves the company was diligent is the same document that proves it knew.

The answer is not to stop documenting. It is that the finding and the remediation have to travel together. A gap register with owners, dates and closure evidence reads as diligence. The same register without the closure column reads as fraction I.

Fraction II addresses gravity, established where the conduct is premeditated and directed at producing negative consequences that transgress the Objetivos Legítimos de Interés Público, affect commerce, or harm a consumer or a specific determined group of consumers. Fraction III addresses economic capacity, evaluated by reference to whether the party is an individual or a micro, small, medium or large enterprise under the classification of the Ley para el Desarrollo de la Competitividad de la Micro, Pequeña y Mediana Empresa and the Ley Federal para el Fomento de la Microindustria y la Actividad Artesanal. A foreign owned plant of any scale sits at the top of that scale by construction.

Article 241 completes the picture: the sanctions of apercibimiento and closure, temporary or definitive, may be executed at any time, and closure may be total, impeding the commercial activity of the whole establishment, or partial, limited to certain areas, places or installations.

What this guide does not tell you

Five things, deliberately.

Amounts. The sanction ranges live in the Ley de Infraestructura de la Calidad, not in this Reglamento. We have not quoted figures here because we have quoted the Reglamento, and putting a number next to article 242 without the Law's own text in front of us would be exactly the kind of confident imprecision this firm tries not to publish.

Whether any article 110 customs alternative exists. We are not aware of one. That is a statement about our knowledge, not a statement that none will be issued, and it is the item most likely to have changed by the time you read this.

Which of your existing documents "se opone" to the new text. The Séptimo makes that determination case by case and provides no procedure for it. It requires reading your actual certificates against a Reglamento published on 4 September, and no general guide can do that.

Your NOM. There are hundreds, they are sector specific, and this Reglamento governs the machinery around them rather than their content. Nothing here tells you what your product must comply with.

What the Ley itself says. This guide is about the Reglamento. Several articles quoted above operate "para efectos de" an article of the Law, and the Law's text controls. Where we have quoted the Reglamento we have quoted it in full; where the Law is doing the work we have said so rather than paraphrasing a text we are not reproducing.

If your operation in Mexico holds certificates, dictámenes or test reports issued before 7 September, there is one question worth asking before anything else, and it is not about your documents:

Who accredited the body that signed them, and when does that accreditation come up for renewal?

Companion analysis

Who accredited the body that signed your certificates?

Tell us which certificates, dictámenes or test reports your Mexican operation relies on today and which bodies issued them. A lawyer will tell you which of them depend on an accreditation now running the three-year clock, and what to ask each body in writing.

A lawyer replies within one business day. Sending this does not create an attorney-client relationship.