Tax Interest: A Structural Asymmetry to the Detriment of Taxpayers

Within the Mexican tax system, the treatment of interest reveals a structural difference that, although technically grounded in statutory and case law criteria, generates relevant practical effects in the relationship between the tax authority and taxpayers.

When the tax authority assesses a tax liability, the amount due is not limited to the principal. It is supplemented with late payment surcharges, inflation adjustments, and, where applicable, penalties, thereby creating a financial cost that increases over time and seeks to compensate the treasury for the lack of timely payment. This mechanism follows a clear rationale: preserving the value of money over time and discouraging non-compliance.

Reversal of the Relationship: When the Taxpayer Becomes the Creditor

However, when the situation is reversed and the taxpayer holds a balance in their favor—whether due to undue payments or the annulment of a tax assessment—the treatment differs. In such cases, refunds issued by the authority do not necessarily incorporate the same comprehensive recognition of the financial cost associated with the time during which the funds were held by the State.

This difference is not minor. From an economic standpoint, it implies that the cost of time is not recognized symmetrically for both parties in the tax relationship. While taxpayers face an interest scheme that may be significant—particularly in inflationary contexts—the authority does not always assume an equivalent cost when it must return funds.

Judicial Criteria and Practical Effects

This situation is reinforced by recent judicial criteria, in which it has been held that the tax authority is not required to pay interest in all refund scenarios, particularly when such payment has not been expressly ordered in a judicial ruling. While this approach is consistent with a strict interpretation of the law, it raises questions from the standpoint of fairness.

In practice, this asymmetry may influence taxpayers’ decision-making, especially in cases where they assess the convenience of challenging a tax assessment or initiating a refund procedure. The financial cost associated with the duration of litigation or administrative processes becomes a relevant factor, not only due to its direct economic impact but also because of the uncertainty surrounding its potential recovery.

Reference and Final Reflection

This topic was addressed in an interview published by the newspaper El Norte, conducted with Gustavo Leal Cueva, partner at Leal Benavides y Compañía, where these considerations and their practical implications for taxpayers were discussed.

Beyond the technical analysis, the discussion invites reflection on the design of the tax system and the way financial risks are allocated between the authority and taxpayers. Consistency in the treatment of interest is not merely a matter of tax technique, but also of balance in the legal relationship that underpins tax compliance.