Mexico’s regulatory agenda accelerated during the week of September 19–25, with several developments requiring immediate attention from tax, customs and compliance teams.
Most importantly, the transition period for the Electronic Value Manifest (Manifestación de Valor Electrónica – MVE) ends on September 30, making the new process mandatory from October 1, 2026. Companies are also approaching an October 31 deadline under the 2026 Tax Regularization Program for final and enforceable tax liabilities.
At the same time, Mexico is progressing with proposed customs reforms, expanding cooperation between financial intelligence and audit authorities, updating electronic invoicing catalogs and strengthening international tax and customs cooperation with South Korea.
Key Developments This Week
Electronic Value Manifest Mandatory From October 1
The Second Resolution of Modifications to the 2026 General Rules for Foreign Trade (Reglas Generales de Comercio Exterior – RGCE), published in the Official Gazette of the Federation (Diario Oficial de la Federación – DOF) on September 22 and effective September 23, confirms that the transitional regime for the Electronic Value Manifest ends on September 30.
The MVE therefore becomes fully mandatory from October 1, 2026.
No further extension has been granted.
October 31 Deadline for Final Tax Liabilities
Mexico’s 2026 Tax Regularization Program provides reductions of up to 100% of penalties and surcharges.
For final and enforceable tax liabilities, taxpayers must submit their applications no later than October 31, 2026, through the Tax Administration Service (Servicio de Administración Tributaria – SAT) Portal.
2027 Economic Package Under Review
Formal working sessions between the Ministry of Finance and Public Credit (Secretaría de Hacienda y Crédito Público – SHCP) and the Chamber of Deputies have begun regarding the proposed new Customs Law and Digital Economy Law.
Mexico’s National Customs Agency (Agencia Nacional de Aduanas de México – ANAM) is also participating in discussions concerning proposed anti-undervaluation measures.
Financial Intelligence Cooperation Expanded
Mexico’s Financial Intelligence Unit (Unidad de Inteligencia Financiera – UIF) and the Superior Audit Office of the Federation (Auditoría Superior de la Federación – ASF) have entered into a new cooperation agreement.
The arrangement expands information sharing aimed at identifying money laundering, corruption and improper use of public resources.
SAT: Electronic Invoicing Catalogs Updated
On September 25, new customs-office/customs-broker-license combinations were added to the c_NumPedimentoAduana catalog under Annex 20.
The additions are:
- Customs Office 11 — Ensenada, Baja California: License 6114
- Customs Office 24 — Nuevo Laredo, Tamaulipas: License 2053
- Customs Office 47 — Mexico City International Airport: Licenses 2053 and 2068
Customs broker license 2053, newly registered as of August 8, 2026, is now formally enabled to operate in Nuevo Laredo and Mexico City International Airport.
Operational Impact
The change is limited but relevant for companies issuing or receiving Digital Tax Receipts via Internet (Comprobantes Fiscales Digitales por Internet – CFDI) that reference customs entries processed by customs brokers holding licenses 2053, 6114 or 2068 at the identified customs offices.
If invoicing systems have not been updated with the catalog version effective September 25, validation errors by Authorized Certification Providers (Proveedores Autorizados de Certificación – PACs) may occur.
There are no changes to the XSD, c_ClaveProdServ, c_TasaOCuota or c_UsoCFDI catalogs.
Recommended action: Companies affected should verify that the latest catalog version has been deployed in their invoicing systems before the next customs clearance cycle.
Mexico and South Korea Expand Tax Cooperation
SAT Head Antonio Martínez Dagnino met with Lim Kwang Hyun, Commissioner of South Korea’s National Tax Service, on September 25.
The discussions covered several areas of tax administration, including:
- CFDI as a core component of Mexico’s digital tax ecosystem;
- the application of big data and artificial intelligence to tax collection and tax-evasion detection;
- international information exchange; and
- taxpayer service models.
Mexico currently operates information-exchange arrangements with 145 countries.
SAT also reported providing 31 million taxpayer services during 2026 through 55 offices and 110 service modules.
South Korea invited Mexico to participate in further working sessions in Seoul, continuing the exchange of tax-administration practices between the two countries.
SAT Mobile Offices
Between September 21 and 25, SAT deployed 69 mobile units across 48 municipalities in 25 states.
The initiative targeted 8,264 taxpayers and 17,101 procedures.
Services available without prior appointment included:
- Federal Taxpayer Registry (Registro Federal de Contribuyentes – RFC) registration;
- electronic signature issuance and renewal;
- Tax Status Certificates; and
- general tax guidance.
The initiative covered Baja California, Mexico City, Chihuahua, Jalisco, Veracruz, Yucatán, Tamaulipas and Michoacán, among other states.
13th Advance Version of the Second Modification to the 2026 Miscellaneous Tax Resolution
Published on September 24, the advance version introduces amendments affecting foreign-resident football players, diesel incentives and authorized donees.
Foreign-Resident FIFA Players
Rule 9.4.4 was amended to establish an option for FIFA Member Associations, excluding the Host Association, to make income tax payments on behalf of foreign-resident players.
The tax must be paid no later than the day following receipt of the income.
Compliance through this mechanism extinguishes the player’s individual filing obligation under Article 170, fourth paragraph, of the Income Tax Law.
Diesel Base-Price Adjustment
Rule 11.7.3 establishes deductions from the diesel base price for periods between July 9 and September 24, 2026.
The applicable amounts range from MXN 0.88 to MXN 0.99 per liter.
The provision is relevant to taxpayers applying the Special Tax on Production and Services fuel incentive under the decree published on December 27, 2016, as subsequently amended.
Authorized Donees
Civil organizations and trusts authorized to receive tax-deductible donations that have been subject to penalties under Article 81, Section XLIV of the Federal Tax Code may retain their authorization for 2027 provided that, by September 30, 2026, they:
- filed their 2025 informational returns;
- paid the applicable penalty; and
- did not challenge the penalty or withdrew any legal challenge already filed.
2026 Tax Regularization Program: Critical Deadlines
The Twenty-Second Transitional Provision of the 2026 Federal Revenue Law establishes a tax regularization program offering relief of up to 100% of penalties, surcharges and enforcement expenses for taxpayers whose 2024 revenues did not exceed MXN 300 million.
Three scenarios apply.
Scenario I – Self-Assessed Unpaid Taxes
The program covers self-assessed unpaid taxes relating to 2024 or earlier years.
The taxpayer must file the corresponding return and make payment in a single installment.
Final deadline: December 31, 2026.
Scenario II – Taxpayers Under Audit
Taxpayers undergoing an audit or other examination may obtain the benefit if they self-correct before the tax authority issues its final assessment.
Payment deadline: December 31, 2026.
Scenario III – Final and Enforceable Tax Liabilities
This is the most immediate deadline.
Applications must be submitted by October 31, 2026 through a clarification case on the SAT Portal.
Payment must be made within 15 calendar days following issuance of the payment reference.
Up to six installments are permitted, with the final installment due by November 30, 2026.
Failure to make an installment causes the tax benefit to lapse. Submission of an application also constitutes full acceptance of the underlying tax liability.
UIF and ASF Strengthen Financial Intelligence Cooperation
On September 22, SHCP, through the Financial Intelligence Unit, entered into a Cooperation Agreement with the Superior Audit Office of the Federation.
The authorities will be able to:
- share financial, asset, tax, budgetary, accounting, administrative and corporate information;
- develop risk models, typologies and joint analytical mechanisms;
- identify structures potentially associated with money laundering, corruption or misuse of public resources; and
- establish a permanent technical working group capable of issuing alerts and risk indicators.
The agreement expands the cooperation framework established in February 2024.
It is particularly relevant for entities receiving government funding or participating in public procurement.
Electronic Value Manifest: No Further Extension
The Second Resolution of Modifications to the 2026 General Rules for Foreign Trade represents one of the week’s most important operational developments.
The amended Eleventh Transitional Provision confirms that the MVE transition period ends on September 30.
From October 1, 2026, the Electronic Value Manifest becomes mandatory for applicable import transactions.
The transmission of Form E15 — Contracts Associated with the Value Manifest — may continue using general contract information through December 31, 2026.
Customs Suspensions and NICO Classification
Rule 1.4.12 changes the procedure for challenging suspension from the Electronic Customs System resulting from an incorrect Commercial Identification Number (Número de Identificación Comercial – NICO) declaration.
Suspended customs brokers and importers will have five days to remedy the issue through either:
- correction of the customs entry; or
- use of a customs guarantee account.
Procedure Form 20/LA, Annex 2 applies.
Authorized Economic Operator Rules
Rules 7.1.4 and 7.1.5 affect the Authorized Economic Operator and Certified Business Partner programs.
The period for remedying non-compliance identified during security-standard inspections has been extended to up to three months from notification.
Where the authority determines that requirements remain unmet, a new application may be submitted after a further six-month period following the resolution.
ANAM Proposes New Anti-Undervaluation Framework
ANAM Head Héctor Alonso Romero Gutiérrez appeared before the Finance Commission of the Chamber of Deputies to present proposed changes to Mexico’s Customs Law.
The proposed measures include:
- elimination of the existing 50% threshold for precautionary seizure based on differences in customs valuation;
- introduction of a new 20% threshold allowing precautionary seizure to be replaced by a guarantee or cash deposit;
- creation of a new Value Intelligence System designed to automatically identify transactions presenting potential undervaluation risks based on the importer, customs broker and industry sector; and
- confirmation that the reform would not modify the temporary import regime or the Manufacturing, Maquiladora and Export Services Industry (IMMEX) program.
Members of Congress raised concerns regarding legal certainty for importers, which ANAM committed to address.
Mexico and South Korea Expand Customs Cooperation
On September 24, ANAM signed a Memorandum of Understanding with the Korea Customs Service.
The cooperation covers:
- exchange of customs information;
- combating drug trafficking and intellectual-property violations;
- identification of triangulated tax-avoidance schemes;
- technology, including non-intrusive inspection equipment and artificial intelligence; and
- facilitation of bilateral Mexico–South Korea customs clearance.
The Korean delegation also visited the Felipe Ángeles International Airport Customs Office to observe Mexico’s non-intrusive inspection systems.
New Judicial Criteria Affect Tax and Labor Matters
Three isolated judicial theses published on September 25 in the Federal Judicial Weekly have implications for Mexican tax and labor practice.
First Sale of Real Estate
Registry 2032645 concerns the notice requirement under Mexico’s anti-money laundering legislation.
The Second Collegiate Circuit Court of the Twenty-Third Circuit held that the exception from the obligation to file a notice on the first sale of real estate applies where either one of two statutory conditions is satisfied, rather than requiring both conditions cumulatively.
Practical impact: Construction and real-estate companies using mixed or bank financing may potentially invoke the exception without demonstrating compliance with both conditions.
Refund of Government Fees
Registry 2032657 concerns construction licenses.
The Fourth Collegiate Circuit Court of the Thirtieth Circuit held that a taxpayer’s decision not to proceed with a construction project does not create a right to a refund of fees already paid for construction licenses.
The principle commonly referred to as “payment of the unjust” applies only where the inability to receive or materialize the service is not attributable to the taxpayer.
Workplace Harassment
Registry 2032686 addresses workplace harassment.
The First Collegiate Court for Civil and Labor Matters of the Seventeenth Circuit held that labor proceedings constitute an appropriate legal avenue for seeking cessation of workplace harassment and nullification of related salary deductions.
Jurisdiction is determined by the nature of the underlying legal relationship rather than the formal name assigned to the claim.
Vulnerable Activities: New UIF Forms
On September 24, the Financial Intelligence Unit published two resolutions updating registration and reporting forms applicable to vulnerable activities.
The changes incorporate:
- customs agencies as a new vulnerable activity;
- public and private facilitators involved in alternative dispute-resolution mechanisms;
- trusts and other legal structures;
- new Annexes 12-C and 14-A; and
- an obligation to submit a notice within 24 hours where money laundering is suspected.
The principal changes become effective on February 1, 2027.
Requirements concerning facilitators apply from June 1, 2027, while suspicious-transaction notice requirements take effect on December 1, 2026.
Northern Border Preferential Tariff Regime Extended
On September 25, Mexico extended the preferential tariff regime applicable to the northern border region and border strip through December 31, 2030.
Existing registrations under the Border Company regime will be automatically renewed.
Countervailing Duties on Steel From Russia and Ukraine
Mexico’s Ministry of Economy extended definitive countervailing duties on imports of hot-rolled steel sheet originating in Russia and Ukraine for five years beginning March 29, 2025.
The applicable rates are:
- Russia: 21%
- Ukraine: 25%
The Ministry determined that there was a well-founded likelihood of recurrence of dumping and injury to ArcelorMittal México and Ternium México, which together account for approximately 85–97% of domestic production.
2026 Labor Inspection Program
Mexico’s Ministry of Labor and Social Welfare has established a target of 38,455 risk-based inspections under its 2026 inspection program.
Since 2019, more than 275,000 inspections have been conducted, affecting approximately 33 million workers.
The 2026 program incorporates the Specialized Services or Works Registry (Registro de Prestadoras de Servicios Especializados u Obras Especializadas – REPSE) 2.0 and new sector-specific inspection protocols.
September 30 Deadline for 2025 Social Security Audit Reports
The Mexican Institute of Public Accountants has reminded employers that the 2025 Social Security Audit Report must be filed by September 30, 2026.
Key compliance considerations include:
- no extension or exceptions;
- verification that employer registrations have not been cancelled under “not located” status;
- electronic filing through the Electronic Social Security Audit System (SIDEIMSS);
- use of Employer Information Template v10.2; and
- valid electronic signatures for both the Authorized Public Accountant and Legal Representative.
Companies subject to the Social Security audit regime should prioritize final validation of registrations, information, templates and electronic signatures to reduce the risk of filing disruption.
Key Compliance Deadlines
September 30, 2026
The 2025 Social Security Audit Report must be submitted through SIDEIMSS using template version 10.2.
Authorized donees affected by relevant penalties must satisfy the conditions necessary to retain their authorization for 2027.
The transitional regime for the Electronic Value Manifest ends.
October 1, 2026
The Electronic Value Manifest becomes mandatory for applicable import transactions.
The pilot Labor Certificate for Agricultural Exports program for avocado exporters also begins.
October 31, 2026
Deadline to apply for relief of up to 100% of penalties and surcharges relating to final and enforceable tax liabilities under the 2026 Tax Regularization Program.
December 31, 2026
Deadline for the first two scenarios under the Tax Regularization Program covering self-assessed unpaid taxes and self-correction during tax examinations.
The option to transmit Form E15 using general contract information also remains available through this date.
What Companies Should Prioritize
For companies operating in Mexico, the immediate focus should be on readiness for the mandatory Electronic Value Manifest from October 1 and identifying whether any final and enforceable tax liabilities qualify for the October 31 Tax Regularization Program deadline.
Tax and customs teams should also review the latest electronic invoicing catalogs, monitor the proposed anti-undervaluation framework and assess whether the expanding exchange of information between Mexican authorities affects their broader compliance and risk-management processes.