Mexico SAT Strengthens CFDI-Based Reviews of Tax Data – Retail Included

Mexico's SAT utilizes digital tax data for preliminary reviews to identify discrepancies before formal audits. This reflects a broader digital enforcement strategy under the 2026 Master Plan, focusing on transparent, risk-based audits. Retailers must ensure consistency between global CFDIs and underlying transactions, as discrepancies can arise from cancellations and returns. Taxpayers have 15 days to address any SAT inquiries or face further auditing procedures. Retailers should reconcile records and retain necessary documentation.

Mexico’s Tax Administration Service, the SAT, continues using digital tax data to identify discrepancies before launching a formal tax audit towards taxpayers.

A recent analysis published last week, describes these initial checks as so called “preliminary reviews,” through which the SAT compares information already available in its systems with the amounts reported by taxpayers. However, this does not represent a newly introduced statutory audit procedure or a new CFDI obligation for businesses. Instead, it actually reflects the SAT’s wider digital enforcement strategy under its 2026 Master Plan, which prioritises completely transparent and risk assessment-based audits focused on taxpayers showing identifiable irregularities.

Particularly, for retailers, the most important source of information is the Comprobante Fiscal Digital por Internet, or CFDI, generated from sales, returns, expenses, payroll and payment transactions.

The SAT’s corporate tax portal provides access to viewers containing information from issued and received invoices, while CFDI data is also used to pre-fill parts of ISR and VAT declarations. This allows the Tax authority to compare declared retail revenue with income CFDIs, VAT amounts, payment records, electronic accounting data, etc.

Therefore, for businesses selling to final consumers, the totals reported through global CFDIs must therefore remain consistent with the underlying-POS receipts and transactions included in the relevant reporting period. What can occur in practice is that differences may arise when cancelled sales, returns, credit notes, individual customer invoices or transactions from individual branches are not correctly reflected in the global CFDI and accounting records.

Particular attention should be paid to transactions initially invoiced using the PPD payment method, as the corresponding CFDI with the payment-receipt complement must be issued when the payment is received.

When the SAT identifies a difference, it may initially send an invitation letter, clarification request or notice asking the taxpayer to explain or voluntarily correct the information. Their official procedure states that taxpayers may generally submit a clarification regarding an omitted-obligation requirement or invitation letter within 15 days of receiving it. If the discrepancy is not resolved, the process of auditing may progress to an information requirement, electronic review or another formal exercise of authorities’ verification powers.

The July 2026 development does not introduce a replacement for CFDI version 4.0, which remains the current invoice format presented through the SAT’s electronic invoicing resources.

Retailers should therefore reconcile POS sales, global CFDIs, individually requested customer invoices, returns, cancellations, payment complements, VAT records and monthly declarations before filing. They should also retain the CFDI XML files, UUIDs, certification records and cancellation acknowledgements needed to demonstrate why the amounts in their internal systems may differ from the preliminary figures calculated by the SAT.