Mexico’s Tax Administration Service (“SAT”) recently published Notice 01/2026, announcing a series of “best practices” that, at least on their face, seek to provide greater transparency, legal certainty, and uniformity in tax audit procedures throughout Mexico during 2026.
Among the most relevant announcements are: (i) the publication of the 2026 Master Plan, “Taxpayer Assistance and Enforcement”; (ii) the rule limiting audits to a single audit per taxpayer in cases of noncompliance; (iii) the use of sampling techniques rather than reviewing 100% of transactions; and (iv) the commitment to apply consistent criteria across all SAT offices nationwide, particularly in areas that have traditionally been controversial, such as unidentified deposits, substance and materiality, deductions, foreign trade, and tax refunds.
However, the same notice makes it clear that tax enforcement in Mexico will become more selective and targeted. The SAT will focus its efforts on taxpayers presenting certain “red flags,” including recurrent tax losses, transactions with companies issuing simulated invoices, inconsistencies between purchases, imports, and sales, abuse of deductions or tax incentives, transactions involving tax havens, improper refund claims, or an effective income tax rate below the average for the relevant industry.
This shift in approach, with fewer but more strategic audits, requires companies operating in Mexico to reassess their level of tax preparedness. A reduction in the number of audits does not imply lower risk; on the contrary, it increases the likelihood of highly technical audits, with a strong emphasis on industry analysis, transaction traceability, and economic substance.
In this context, having a preventive tax strategy, conducting tax risk assessments, and maintaining a robust defense for potential audits has become essential.