September 11, 2025
The new version 3.6.7 of the Sistema Único de Autodeterminación (SUA), available as of August 22, 2025, through the Instituto Mexicano de Seguridad Social (IMSS) website, incorporates various changes to comply with the reform of Article 29 of the Instituto del Fondo Nacional de la Vivienda para los Trabajadores (INFONAVIT), published in the Official Gazette of the Federation on February 21, 2025, has technical flaws and errors.
Given the reported inconsistencies, the institutions responsible for providing social security services have unofficially announced that employers who downloaded version 3.6.7 before August 27 must download the SUA.EXE file and reinstall it.
It is important to mention that the update of this tool, which allows employers to calculate and report employee-employer contributions to the IMSS, as well as their workers’ contributions to INFONAVIT, presents, among others, the following inconsistencies:
– When the worker’s salary is not sufficient to cover the full amount of the Infonavit loan, the system marks “insufficient withholding.”
– It requires the employer to provide an “employer clarification within 10 to 12 days,” a procedure that is not provided for in the law.
– Although the SUA does not convert the difference into a direct debit for the employer, it does leave the payment in a “default” status and creates legal uncertainty.
– Error messages when attempting to restore backups, no payment lines are generated, and errors when calculating amortization.
This leaves companies exposed to reviews and possible changes in INFONAVIT’s criteria. Therefore, we believe that the next bimonthly payment of Infonavit loans through the SUA becomes the first practical act of application of the reform, opening a second opportunity to seek an injunction.
We remain at your service to advise you on compliance with this new obligation.
Sincerely,
Gil Zenteno
Jorge G. De Presno
Gerado Nieto
David Puente Tostado
José Miguel Tuirán
Ana Sofia Lazcano
Gabriela Méndez
Jesús Carmona