Following the amendment to Mexico’s Customs Law published on November 19, 2025 (effective as of January 1, 2026), compliance obligations of importers and exporters in Mexico have increased significantly, particularly with respect to substantiation and traceability of international trade transactions.

Under this reform, companies operating in Mexico must maintain sufficient legal, operational, and financial support to evidence the real and verifiable existence of each transaction. It is no longer sufficient to rely solely on the customs entry and its standard annexes. Mexican customs authorities will now require documentary proof that the transaction occurred as stated, that the company had the necessary productive capacity, that funds were effectively transferred, and that the entire process is fully traceable.

Specifically, pursuant to Article 59, Section V of Mexico’s Customs Law, as well as Rule 3.1.42 of the Mexican General Foreign Trade Rules (“RGCE”), companies must create and maintain a digital file for each import or export transaction. In addition to the customs entry and commercial invoice, this file must include documentation supporting the resources used in the transaction, such as agreements and contracts, electronic tax invoices, proof of payment, logistics expenses, asset support documentation, evidence of services rendered, information regarding personnel involved, technical data sheets, and inventory control records.

The obligation becomes particularly sensitive in the case of “virtual” operations under Mexico’s IMMEX framework, where Rule 4.3.22 requires companies to substantiate the production process from the moment of temporary importation through the transfer of goods, without breaking the documentary chain of custody. This may entail the exchange of strategic or commercially sensitive information between related or unrelated companies operating in Mexico.

The preparation and maintenance of these digital transaction files will require a high level of internal control and cross-functional coordination among customs compliance, finance, production, warehouse, and human resources departments. Based on our recent experience, many organizations are not yet fully prepared to meet these enhanced requirements. Non-compliance may result in fines, tax assessments, and significant risks to a company’s VAT and Excise Tax Certification (IVA-IEPS), Mexico’s Importers Registry, and even its IMMEX authorization.

Given the scope of these new requirements in Mexico, we strongly recommend that companies begin internal training and compliance alignment efforts immediately. In this context, we have developed a specialized intensive course designed to translate the digital file requirements into practical processes and to support the development of an internal compliance plan tailored to Mexican customs regulations.

We are available to provide further information regarding these new compliance obligations and our training program.