Mexico's Electronic Customs Value Declaration (MVE): What Changes On August 1

From 1 August 2026, Mexico requires the customs value declaration, the Manifestación de Valor, to be filed electronically through the VUCEM single window using an electronic form, ending the transitional grace period on 31 July 2026. It is the importer's legal obligation, transmitted in practice by the Mexican customs broker, and it documents how the declared customs value was determined. Because Mexico's tax authority has postponed this date several times, treat 1 August as the current deadline, subject to a possible further extension, and confirm before acting.

• The Manifestación de Valor is the customs value declaration required of importers under Mexico's Ley Aduanera (Article 59, section III).
• From 1 August 2026 it must be submitted electronically through VUCEM (Mexico's single window for foreign trade); the transitional grace period ends 31 July 2026 (SAT, ANAM).
• During the transition, two mechanisms coexist: the electronic form via VUCEM, or retaining the traditional supporting documentation; non-transmission is not treated as non-compliance during the window.
• The obligation rests on the importer, but the customs broker (agente aduanal) transmits it as part of clearance.
• Mexico's SAT has extended this deadline several times, so the 1 August 2026 date is current but could shift again; verify before relying on it.

What is changing on 1 August 2026?

The customs value declaration, the Manifestación de Valor, moves from a document you keep on file to a mandatory electronic filing through Mexico's VUCEM single window. The transitional grace period, during which either the electronic form or traditional documentation was accepted, ends on 31 July 2026.

Every import into Mexico has always required a customs value declaration, the Manifestación de Valor, which is the importer's formal statement of how the declared customs value of the goods was determined. What is changing is not the obligation itself but the way it is filed. Under a change introduced through the Second Amendment to the 2026 General Foreign Trade Rules, this declaration must be submitted electronically through VUCEM, Mexico's single window for foreign trade, using the designated electronic form, and that electronic filing becomes mandatory on 1 August 2026. Until then, a transitional grace period runs through 31 July 2026, during which two mechanisms coexist: an importer can either transmit the electronic form via VUCEM or continue to rely on retaining the traditional supporting documentation, and not transmitting the electronic version during this window is not treated as non-compliance. After the grace period, the electronic route becomes the required one. For a US company shipping into Mexico, the practical takeaway is that this is a compliance and documentation change on the Mexican side of the border, handled through your Mexican customs broker, not a new tax or tariff. One important caveat runs through everything below: Mexico's tax authority, the SAT, has postponed this deadline more than once, so 1 August 2026 is the current date but could move again, and any date here should be confirmed against SAT before you act. BringGo Ship clears shipments into Mexico through its licensed broker, who handles the electronic value declaration as part of the clearance it already manages.

Who is responsible, and what does the declaration cover?

The obligation is the importer's, under Article 59 of the Ley Aduanera, but in practice the Mexican customs broker transmits the declaration during clearance. It documents how the customs value was determined, the transaction value, the commercial terms, any adjustments, and related-party status, so it supports the value declared on the pedimento.

It helps to be clear about who carries the obligation and what the declaration actually contains, because that determines what you need to provide. Legally, the Manifestación de Valor is the importer's obligation, rooted in Article 59, section III of Mexico's Ley Aduanera and the corresponding foreign-trade rules; it is the importer who must be able to substantiate the customs value of the goods. In practice, though, the Mexican customs broker, the agente aduanal, is the one who transmits the declaration electronically as part of the customs clearance it performs on the importer's behalf, so for most US shippers this happens through the broker rather than being a separate task they file themselves. What the declaration covers is the basis of the customs value: the transaction value of the goods, the commercial terms of sale, the elements added to or excluded from the price under Mexico's valuation rules, and whether the buyer and seller are related parties, all of which together support the value declared on the pedimento. This matters because the whole point of formalizing and digitizing the declaration is to give customs a clearer, auditable record of how values were built, which is part of a broader Mexican enforcement focus on the undervaluation of imports. For a US shipper, the message is that the commercial invoice and supporting documents need to be accurate and consistent, because they feed the value declaration your broker transmits. BringGo Ship's broker prepares and transmits this declaration using the documentation you provide, which is why keeping the invoice and value support clean and consistent matters more than ever.

What should a US shipper do before the deadline?

Confirm that your Mexican customs broker is set up to transmit the electronic value declaration through VUCEM, make sure your commercial invoices and value documentation are accurate and consistent, and treat 1 August as the current deadline while checking for any further SAT extension. If you clear through an operator that manages the Mexican side, this is largely handled for you.

The good news for a US shipper is that this change is mostly operational and sits with your Mexican-side clearance, so preparing for it is straightforward. First, confirm that whoever clears your goods in Mexico, your customs broker, is ready to transmit the electronic value declaration through VUCEM, because after the grace period ends the electronic route is the one that keeps your shipments moving; an operator that runs clearance daily will already be moving to this. Second, tighten your documentation: because the declaration substantiates the customs value, your commercial invoice, the stated terms of sale, and any value adjustments need to be accurate and internally consistent, since inconsistencies are exactly what a formalized, digitized value record is designed to surface. Third, treat 1 August 2026 as the current deadline but stay alert, because SAT has extended this obligation several times, most recently to this date, so a further postponement is possible though not confirmed, and you should verify the live status rather than assume. Fourth, do not overreact: this is a customs-compliance and documentation change, not a new duty or tax, so there is no rate to recalculate, only a filing to be ready for. If you ship through an operator that owns the Mexican side of clearance, the practical work of transmitting the declaration is handled within the clearance you already rely on. BringGo Ship clears shipments into Mexico through its licensed broker on the Laredo-Monterrey lane, transmitting the value declaration as part of that process, so a US shipper is ready for 1 August without building anything new.

Mexico's value declaration: before and after 1 August 2026

Definitions

• Manifestación de Valor (MVE): The Manifestación de Valor is Mexico's customs value declaration, the importer's formal statement of how the declared customs value of imported goods was determined.
• VUCEM: VUCEM is Mexico's single window for foreign trade, the electronic platform through which the value declaration must be filed from 1 August 2026.
• Agente aduanal: The agente aduanal is the licensed Mexican customs broker who transmits the value declaration and files the pedimento on the importer's behalf.

Frequently asked questions

What is Mexico's Manifestación de Valor?

It is the customs value declaration required of importers under Mexico's Ley Aduanera (Article 59, section III), the importer's formal statement of how the declared customs value of the goods was determined. It documents the transaction value, commercial terms, adjustments and related-party status that support the value on the pedimento.

What changes on 1 August 2026?

The declaration must be filed electronically through Mexico's VUCEM single window, and that electronic filing becomes mandatory. The transitional grace period, during which either the electronic form or traditional documentation was accepted, ends on 31 July 2026. It is a filing-method and documentation change, not a new tax or tariff.

Do I have to file it myself as a US shipper?

No. The obligation is legally the importer's, but in practice the Mexican customs broker transmits the declaration electronically as part of clearance. Your main job is to provide accurate, consistent commercial invoices and value documentation, which feed the declaration your broker files.

Could the 1 August 2026 deadline change again?

Yes, possibly. Mexico's SAT has postponed this obligation several times, most recently to 1 August 2026, so a further extension is possible though not confirmed. Treat 1 August as the current deadline, and verify the live status with SAT or your broker before acting rather than assuming it is fixed.

Is this a new import tax?

No. It is a customs-compliance and documentation change, not a duty or tax. There is no new rate to calculate. It formalizes and digitizes how the customs value is declared and substantiated, which is part of Mexico's broader focus on the undervaluation of imports.

How do I get ready before the deadline?

Confirm your Mexican customs broker is set up to transmit the electronic value declaration through VUCEM, make sure your invoices and value documentation are accurate and consistent, and check for any further SAT extension. If you clear through an operator that owns the Mexican side, this is largely handled within your existing clearance.

Clear into Mexico with a broker ready for the electronic value declaration

Sources

• SAT (Mexican tax authority) (sat.gob.mx)
• ANAM (national customs agency) (gob.mx)
• VUCEM (single window) (ventanillaunica.gob.mx)

Note: This content is for general information only and is not legal, tax or customs advice. Rates and rules can change often in 2026; verify the current details with an official source (SAT, DOF, CBP) or our licensed customs broker before acting.