Mexico's Second RGCE 2026 Amendments: Electronic Customs Value Declarations and Transitional Document Relief

Mexico’s move to an electronic manifestación de valor (customs value declaration) is a defining compliance issue for anyone importing goods into Mexico. Amendments to the Reglas Generales de Comercio Exterior (RGCE) have progressively made electronic filing the standard channel for the value declaration, while providing transitional easements to smooth the shift away from paper. For importers, brokers and multinational groups, the practical message is clear: the paper route is being phased out, the electronic route is the accepted channel, and any transitional easements must be used correctly before they lapse. This article explains what the electronic value-declaration regime requires, who is responsible, and the concrete steps to take.

Key takeaways at a glance

• Electronic filing of the value declaration is the standard. The paper manifestación de valor has been phased out under the electronic regime; verify the exact effective date in the applicable DOF resolution.
• Transitional relief may apply for a limited period. Certain transport, origin and customs-account guarantee documents need not be transmitted separately when they travel as electronic annexes to the pedimento. Confirm the current window before relying on it.
• Format E15 may be used to declare contract data bajo protesta de decir verdad (under oath) where the applicable rules permit.
• Customs agencies and individual agents must maintain an electronic client file.
• Certification applicants and holders have a defined window to report remedied security-standard shortcomings to AGACE.

The mandatory switch to electronic value declarations

The central change is the move away from paper as an accepted method for the manifestación de valor toward a fully electronic channel. The operational effect is straightforward but consequential: paper value declarations are being phased out, and the electronic manifestación de valor becomes the sole valid route on the effective date set by the applicable amending resolution. Operators should confirm the precise cut-off date in the current DOF text, because the transition applies uniformly across import operations and there is generally no discretionary extension for individual operators.

The legal architecture sits within the RGCE, which operationalise the Ley Aduanera and its Reglamento. The relevant changes are reflected across the RGCE annexes, practitioners should read the amendment alongside the annexes that govern formats, definitions and the data fields carried in the pedimento (notably Annexes 1, 2 and 22). Because the value declaration underpins customs valuation, the shift to a fully electronic channel is not a mere administrative formality: it changes the evidentiary and audit trail that supports every declared customs value.

Who is responsible for filing the electronic manifestación de valor?

Responsibility for the manifestación de valor ultimately rests with the importer, who declares the customs value of the goods. In practice, the customs broker (agente aduanal) or customs agency executes the electronic transmission on the importer’s behalf. This division of labour makes clear contractual allocation essential. The importer must supply accurate, complete and timely valuation data, including contract terms, transport costs and any additions to price, while the broker is responsible for correctly formatting and transmitting that data through the electronic system. Neither party can rely on the other to absorb a compliance gap: an incorrect or missing electronic declaration exposes the importer to valuation adjustments and the broker to professional and administrative consequences.

Technical format and validation checks

The electronic manifestación de valor is submitted through the systems maintained by the Servicio de Administración Tributaria (SAT) and its customs authority (the Agencia Nacional de Aduanas de México, ANAM, which now administers many operational customs functions alongside SAT). Filings are validated against the technical specifications published by the authorities, including the XML structure and data fields referenced in the relevant annex. Importers and brokers should confirm that their software and service providers have implemented the latest schema, because a filing that fails validation will be rejected, and a rejected value declaration can delay or block clearance. Before the first live filing under the new regime, teams should run test transmissions against official technical guidance to catch formatting errors early.

Transitional document relief: scope and limits

Alongside the mandatory switch, the electronic regime typically includes a deliberate easement to smooth the transition. During the applicable transitional period, importers may not be required to transmit certain supporting documents as separate electronic transmissions where those documents already travel as electronic annexes attached to the pedimento. The relief generally covers transport documentation, proof of origin, and customs-account guarantee documents, the categories associated with the fractions of article 81 of the Reglamento de la Ley Aduanera. The rationale is practical: if the document is already captured and carried electronically with the customs declaration, requiring a duplicate standalone transmission adds friction without adding assurance. Confirm the exact scope, the qualifying document categories and the closing date in the current DOF text.

This relief is temporary, and its scope is precise. It does not abolish the obligation to hold and be able to produce these documents; it simply spares operators the separate transmission step while the electronic annexing workflow beds in. Operators who misread the relief as a licence to omit documentation entirely will find themselves exposed once authorities request the underlying evidence during a review or audit.

What annexes qualify as “electronic annexes to the pedimento”?

To benefit from the relief, the transport, origin and guarantee documents must genuinely travel as electronic annexes to the pedimento, that is, they must be attached to and transmitted with the customs declaration itself, not merely stored on the importer’s or broker’s own systems. The document must be legible, complete and correctly associated with the relevant pedimento. If the annex is missing, corrupted or unlinked, the relief does not apply and the operator reverts to the standard transmission requirements. Brokers should verify, on every operation during the window, that each qualifying document is properly attached before the pedimento is transmitted.

Using format E15, content requirements and sample phrasing

Where the applicable rules permit, importers may declare contract data using format E15 bajo protesta de decir verdad during the transitional period. This means that, rather than furnishing the full contractual documentation as a separate transmission, the importer may provide the relevant contract information in the E15 format, affirming its truthfulness under oath. The declaration carries real legal weight: a statement made bajo protesta de decir verdad that proves false can trigger administrative penalties and undermine the declared customs value.

A sample phrasing an importer might adapt for an E15 declaration, to be validated against official technical requirements before use, reads:

“Bajo protesta de decir verdad, manifiesto que los datos del contrato aquí declarados corresponden fielmente a la operación de compraventa que sustenta el valor en aduana de la mercancía amparada por el pedimento referido, y que la información es veraz, completa y verificable.”

In English: “Under oath, I declare that the contract data stated here faithfully corresponds to the sale transaction supporting the customs value of the goods covered by the referenced pedimento, and that the information is truthful, complete and verifiable.” Importers should ensure the underlying contract remains on file and reconciles precisely with the declared data.

Limits and pitfalls, when the relief does not apply

The relief has hard edges. It does not apply after its closing date, and it does not apply where the qualifying documents are not properly attached as electronic annexes to the pedimento. It does not relieve importers of the substantive obligation to declare the correct customs value, nor does it protect a false E15 declaration. Operators should also remember that the relief addresses transmission mechanics, not evidentiary standards: authorities can still demand the underlying transport, origin and guarantee documents during a review. Treating the easement as a permanent simplification, rather than a bridge, is the most common and most costly misreading.

Document flow example under the transition

Comparison, paper vs electronic manifestación de valor and transitional relief

Duty for customs agencies and individual customs agents: the electronic client file requirement

A further pillar of the electronic package is a duty on customs agencies and individual customs agents to maintain an electronic client file (archivo electrónico del cliente). This obligation formalises what many diligent brokers already do informally, but it raises the compliance bar by making an organised, accessible electronic record a regulatory requirement rather than a matter of good practice.

The electronic client file should capture the information necessary to identify the client, evidence the engagement and support the operations transmitted on the client’s behalf. In practice, that means client identity and tax records, the engagement or mandate authorising the broker to act, and the documentation underpinning each customs operation. Files must be maintained in an accessible electronic form so that they can be produced to the authorities on request, and retained for the periods contemplated by the Ley Aduanera and its Reglamento.

Practical steps for customs agencies and brokers to comply

• Map your data. Identify what client and operational records you already hold and where they sit.
• Centralise and structure. Consolidate records into a searchable electronic repository indexed by client and by pedimento.
• Set retention and access controls. Apply retention periods consistent with customs regulation and restrict access to authorised personnel.
• Build an audit trail. Log who accessed or amended each file, so the authorities can rely on the integrity of the record.
• Document your governance. Adopt an internal policy describing how the electronic client file is created, maintained and produced.

Client communications, sample authorisation clause

Brokers should update engagement letters to reflect the electronic client file duty and to secure client consent to hold and process the relevant records. A sample clause, to be reviewed by counsel before use, reads:

“The Client authorises the customs agency/agent to create and maintain an electronic client file containing the identification, contractual and operational records necessary to comply with the Reglas Generales de Comercio Exterior and applicable customs law, and to produce such records to the competent authorities upon request.”

Certification applicants and holders: the reporting obligation to AGACE

The RGCE also address certification. Applicants for, and holders of, customs certifications (including the various certificación en materia de IVA e IEPS and OEA-type schemes) must report to the Administración General de Auditoría de Comercio Exterior (AGACE) when they have remedied shortcomings identified against the applicable security standards. The obligation is time-bound, with a defined reporting window; confirm the exact number of days in the current rule text. This affects certified operators and those seeking certification, for whom maintaining the underlying security standards is a condition of their status.

Failing to report within the applicable window can jeopardise the certification itself, exposing the operator to review, suspension or refusal. Because certified status often unlocks operational benefits and streamlined treatment, the practical cost of missing the deadline can be significant and disproportionate to the effort of a timely report.

How to structure remediation reports to AGACE

A remediation report should be clear, evidenced and complete. It should identify the specific security-standard shortcoming that was flagged, describe the corrective action taken, evidence that the action has been implemented, and state the date on which the remedy was completed so that AGACE can confirm the reporting window was observed. Attaching supporting documentation, updated procedures, records or photographs where relevant, strengthens the report and reduces the risk of follow-up queries.

Interaction with certification renewal and suspension risk

Timely, well-evidenced reporting protects the continuity of certification. A pattern of missed or incomplete reports signals weak internal controls and increases the likelihood of adverse action at renewal. Operators should assign clear internal ownership of AGACE reporting, integrate it into their compliance calendar, and treat the reporting window as a hard deadline rather than a target.

Cross-border and exporter implications

The reach of the electronic value-declaration requirements extends beyond Mexican borders. Foreign exporters and multinational groups selling into Mexico must ensure their documentation supports the electronic annexing workflow their Mexican importers now depend on. If a foreign seller supplies transport, origin or contract documentation in a format that cannot be cleanly attached as an electronic annex to the pedimento, the importer loses the benefit of any transitional relief and faces avoidable delay.

For corporate groups, the change intersects with intercompany pricing. Because the value declaration underpins customs valuation, transfer-pricing arrangements and the contracts that document them must reconcile with what is declared electronically, and, during any transition, with any contract data submitted through format E15. International valuation principles reflected in the World Customs Organization and World Trade Organization frameworks continue to inform Mexican practice, but the operational implementation is now firmly electronic.

Practical checklist for foreign sellers and logistics providers

• Supply commercial and transport documents in legible electronic formats compatible with pedimento annexing.
• Ensure contract terms match the customs value your importer will declare.
• Coordinate with the importer’s customs broker on timing and file specifications.
• Align intercompany documentation with the declared value to withstand a valuation review.
• Confirm your logistics partners can deliver documents in time for electronic attachment before transmission.

Immediate actions for importers and brokers

Importers and brokers should work through a prioritised action list rather than a general review. The steps below are sequenced by urgency.

1. Now: Confirm in writing which party files the electronic manifestación de valor and that the broker’s systems are ready.
2. Early: Test electronic annexing on live or sample pedimentos to confirm transport, origin and guarantee documents attach correctly.
3. Before each transition operation: Verify E15 contract data reconciles with underlying contracts before transmitting under oath.
4. Before the relief closes: Prepare for the end of any transitional easement by moving to full standard transmission and evidentiary practice.

Confirm brokers will file the electronic value declaration

Send your broker a short confirmation request. A sample email reads: “Please confirm that you will transmit the electronic manifestación de valor for all our operations, that your systems meet current SAT/ANAM validation requirements, and that you will attach transport, origin and guarantee documents as electronic annexes to the pedimento during any applicable transitional period.” Retain the reply as part of your audit trail.

Check electronic annexes on the pedimento

For each operation, verify that qualifying documents are attached, legible and correctly linked before transmission. Keep a per-pedimento checklist recording that each annex was confirmed present, so that if the authorities request evidence you can demonstrate a consistent process rather than an ad hoc one.

Review certification compliance and the AGACE reporting process

Assign an internal owner for AGACE reporting, document the reporting workflow, and diarise deadlines the moment a security-standard shortcoming is remedied. Certification is too valuable to lose on a procedural miss.

What to do if your broker is not ready

If a broker cannot file the electronic manifestación de valor or attach electronic annexes correctly, treat it as a live risk. Escalate the issue in writing, consider engaging an alternative broker with proven electronic capability, and where clearance is at risk, coordinate with the customs authority rather than proceeding on a defective filing that could be rejected or challenged.

Compliance risks, penalties and remedial measures

Non-compliance under the electronic value-declaration regime carries administrative exposure. An incorrect or missing electronic value declaration can trigger valuation adjustments and administrative penalties; a false E15 declaration made bajo protesta de decir verdad compounds the risk; and failure to maintain the electronic client file or to report to AGACE within the applicable window exposes brokers and certified operators to enforcement and to certification risk. Because the value declaration drives customs valuation, errors here tend to ripple across duties, taxes and downstream compliance.

Typical enforcement scenarios and mitigation strategies

Common scenarios include rejection of a filing that fails validation, a request for documents where relief was assumed but annexes were not properly attached, and a valuation review where declared contract data does not reconcile with the underlying contract. Mitigation is largely preventive: file correctly, keep complete records, and reconcile E15 data against contracts before submission. Where an error surfaces, prompt engagement with the authority, regularisation of documentation, and, where available, voluntary disclosure will generally place an operator in a stronger position than waiting for the issue to be raised.

Sources and how to read the RGCE amendments

The authoritative text is the applicable Resolución de Modificaciones a las Reglas Generales de Comercio Exterior, published in the DOF. To locate it, search the DOF by publication date and title. Read it alongside the RGCE annexes that govern formats, definitions and the pedimento data fields. Cross-reference any transitional relief with article 81 of the Reglamento de la Ley Aduanera via the Cámara de Diputados legislation repository, and consult SAT/ANAM customs technical guidance for XML specifications and filing mechanics. For international valuation context, the World Customs Organization and World Trade Organization resources remain the reference frameworks. Because effective dates and transitional windows are set in the specific resolution, always verify the current provisions before relying on them.

Conclusion and recommended next steps

Mexico’s electronic value-declaration regime is a decisive shift: electronic filing of the manifestación de valor is the standard, transitional document relief is time-limited, and duties on electronic client files and AGACE reporting apply to brokers and certified operators. Importers and brokers should confirm filing responsibility, test electronic annexing, use format E15 carefully, and prepare for the end of any relief. For tailored advice on your operations, and to confirm the current effective dates and transitional windows applicable to you, contact a Global Law Experts corporate specialist in Mexico via the Mexico, Corporate practice area or the GLE Lawyer Directory for Mexico, Corporate.

Sources

1. Diario Oficial de la Federación (DOF)
2. Servicio de Administración Tributaria (SAT)
3. Agencia Nacional de Aduanas de México (ANAM)
4. Cámara de Diputados, Legislación (LeyesBiblio)
5. Secretaría de Economía
6. World Customs Organization (WCO)
7. World Trade Organization (WTO)
8. Tribunal Federal de Justicia Administrativa (TFJA)
9. Barra Mexicana, Colegio de Abogados