Reform to the Federal Tax Code (CFF) 2026: A CFDI Is No Longer Enough If the Transaction Is Not Real

For years, compliance with Mexico’s Digital Tax Receipts (CFDI) was assessed primarily from a technical standpoint: correct stamping, aligned catalogs, valid XML structure, and fulfillment of formal requirements.
If the receipt passed these validations, it was assumed that the tax obligation had been met.

This approach changes significantly with the Reform to the Federal Tax Code (CFF), published on November 7, 2025, and effective as of January 1, 2026.

From now on, CFDIs are reviewed not only based on how they are issued, but on what transaction they actually support.
This is not a format change.
It is a change in criteria and in the level of scrutiny.

The Reality of the Transaction as an Express Tax Requirement

With the incorporation of section IX into Article 29-A of the CFF, the law explicitly establishes that CFDIs must document real transactions, understood as existing, true transactions or legal acts that were effectively carried out.

This new requirement does not replace the previous ones:
the CFDI must still comply with all technical and tax elements, but it must also correspond to a transaction that actually occurred and that can be substantiated before the tax authority.

The validity of a CFDI is no longer assessed solely through the XML.
Correct stamping alone no longer fulfills compliance.

Formal Compliance Is No Longer Sufficient

One of the most relevant aspects of the reform is that formal CFDI compliance, by itself, is no longer enough.
Even if a receipt is correctly stamped and meets all technical parameters established by the SAT, the taxpayer must be able to demonstrate the truthfulness and materiality of the transaction documented, in the event of an audit.

The focus of the analysis expands:
from the receipt itself to the transaction that gave rise to it.

Presumption of Falsity and Summary Procedure: Scope of Article 49 Bis

When the authority detects possible inconsistencies regarding the reality of a transaction, it may initiate a summary procedure in accordance with Article 49 Bis of the CFF.

In this scenario, the SAT is empowered to presume that the transactions documented in the CFDIs are false and to order an audit visit, which may be carried out at:

• The taxpayer’s tax domicile
• Establishments, offices, or warehouses
• Fixed or semi-fixed points of sale
• Locations where the activities supported by the CFDIs are carried out

From the moment the order is notified, the authority may suspend the issuance of the involved CFDIs until a final resolution is issued.

During the audit, inspectors may document facts through photographs, audio recordings, or videos.

Short Deadlines and Burden of Proof on the Taxpayer

This procedure is characterized by its speed.
The taxpayer or the person attending the audit has five business days to submit evidence and arguments to rebut the presumption of falsity.

The evidence must be directly related to the reviewed transaction and may include:

• Accounting records
• Contracts and supporting documentation
• Operational evidence
• Photographs, videos, or other elements proving the reality of the transaction

Once this period has elapsed, the authority has fifteen business days to issue and notify its resolution.

Overall, the procedure may be concluded in less than one month.

Possible Resolutions and Tax Consequences

The process may conclude in one of two ways:

• Favorable resolution, when the taxpayer successfully proves the reality of the transaction. In this case, the suspension of CFDI issuance is lifted.
• Unfavorable resolution, when the presumption is not rebutted. The CFDIs are considered false with general effects, and the transactions produce no tax effects.

Additionally, the SAT may:

• Publish the taxpayer’s name and tax ID (RFC) on its website and in the Official Gazette of the Federation.
• Initiate additional procedures in accordance with the CFF.

The Impact Also Reaches CFDI Recipients

The reform does not affect only the issuer.
Recipients of CFDIs declared false must reverse the applied tax effect by filing an amended tax return within 30 calendar days following the corresponding publication.

If this correction is not made on time, the SAT may temporarily restrict the recipient’s Digital Seal Certificate (CSD).

Other Relevant CFDI-Related Adjustments

This new approach is accompanied by additional measures that strengthen tax control:

• The deadline for CFDI cancellation is redefined, allowing cancellation up to the month of filing the annual income tax return, with the recipient’s acceptance.
• Conditioning CFDI issuance on the presentation of the Tax Identification Card or Tax Status Certificate is prohibited.
• Penalty amounts for non-compliance with the CFF are adjusted.
• New grounds for restriction and cancellation of the Digital Seal Certificate are incorporated.
• New crimes related to the issuance, acquisition, or tax use of CFDIs declared false are created.

2026 Establishes a More Demanding Compliance Standard

The reform does not create a new type of CFDI nor does it modify its technical structure.
What it does is raise the standard of tax auditing, placing coherence between the receipt and the real transaction that supports it at the center.

As of 2026, correct issuance remains essential, but it is no longer sufficient.
Traceability, documentation, and operational consistency are consolidated as key elements of tax compliance.

Are your processes ready for this new level of tax scrutiny?

At LLB Solutions, we help companies structure controls, processes, and technology solutions that support the reality of transactions and reduce tax risks.

Let’s talk and assess your level of readiness for the 2026 Reform.

info@llbsolutions.com | Localización México