The June 2026 DIOT often seems like an administrative task, but it is actually a consistency test between suppliers, XML files, accounting, banks, and VAT. If the company reports operations without reconciling, it can create discrepancies that later take time to explain.

Reconcile by supplier before reporting

Group transactions, VAT and payments by supplier RFC and compare them with the ledger and VAT return. Isolate partial payments, replacement CFDI and missing supplier data instead of forcing the total to match. If June is already filed, use the same reconciliation to confirm the evidence and decide whether a correction is required.

The SAT maintains the process to submit the Informative Declaration of Operations with Third Parties. Before using it, it is advisable to verify that the input VAT does not depend solely on downloaded invoices but on real, classified, and supported operations.

What must be reconciled before submitting

DataWhat to checkRisk if missing
SupplierRFC, business name, and type of operation.Reporting inconsistent or duplicate data.
Input VATBase amount, rate, payment, and accounting treatment.Claiming VAT without sufficient support.
WithholdingsAmount withheld and related CFDI.Discrepancies against monthly declarations.
XMLCFDI valid, canceled, or replaced.Reporting invoices that no longer support the operation.

Sensitive point

Not all received XML files should automatically become input VAT. First, there must be an operation, payment when applicable, and correct tax treatment.

Common mistakes

  • Using the bulk CFDI download without cross-checking against bank payments.
  • Not separating suppliers by type of operation when applicable.
  • Leaving canceled invoices within the operations summary.
  • Recording withholdings in accounting but not reconciling them against the supplier.

Recommended process for June

  1. Download received CFDI and separate canceled, replaced, and valid ones.
  2. Cross-check suppliers against bank records and accounting entries for the period.
  3. Classify operations with VAT, exempt, zero rate, and withholdings.
  4. Review discrepancies against the monthly VAT declaration.
  5. Save working file, acknowledgment, and evidence used for submission.

How Fintax can help

Fintax can review your supplier summary, XML files, payments, and VAT declaration so that the DIOT is supported. The goal is to report accurately, not just fill in fields.

Official links to complete the task

Open official services from a new browser tab, confirm the taxpayer and period, and save the resulting acknowledgment or evidence with the case.