IMSS mandates SAT e. firma for employer digital procedures

The Mexican Social Security Institute (IMSS) has mandated the use of the e. firma, issued by the Tax Administration Service (SAT), for various employer and affiliation procedures via its digital platforms. This measure, approved by the IMSS Technical Council and published in the Official Gazette of the Federation on July 16, aims to strengthen security and identity verification for electronic services.

Under this new scheme, employers and legal representatives must use a valid e. firma, which will replace the Electronic Employer Identification Number (NPIE) as the primary access mechanism for certain services. Experts recommend that companies verify the validity of their digital signatures and ensure authorized personnel have the necessary access to the Virtual Desk to avoid delays in administrative movements.

To facilitate fiscal authentication, the SAT offers a portable e. firma through the SAT Móvil application. This tool allows users to generate a dynamic key using two-factor authentication—the SAT password and a dynamic code—eliminating the need to carry physical USB drives containing certificate files.