e.firma for MVE: requirements and signing process

Why e.firma is mandatory for the MVE

The MVE is a declaration under oath. For legal validity, it must be electronically signed by the importer. The e.firma (formerly FIEL) is the digital certificate issued by SAT that has the same legal value as a handwritten signature.

How to obtain your e.firma

1. Generate your private key and certificate request in SAT's Certifica tool
2. Schedule an appointment at your nearest SAT office
3. Attend with official ID, CURP and proof of address
4. SAT will deliver your certificate (.cer) and private key (.key)
5. The e.firma is valid for 4 years for both companies and individuals

Renewing your e.firma

If your e.firma is valid but expiring soon, you can renew it online through the SAT portal without visiting an office. If already expired, you must process it again with an in-person appointment.

Difference between e.firma and VUCEM digital seal

The e.firma belongs to the importer and is used to sign the MVE. The VUCEM digital seal belongs to the customs broker and is used to sign the COVE. They are two different certificates issued by different entities (SAT vs VUCEM). They are not interchangeable.

How Camtom signs the MVE with your e.firma

Camtom allows you to securely upload your .cer certificate and .key file. When transmitting the MVE, you enter your password and Camtom signs the document and sends it to VUCEM. Your private key is never stored; it is used only at the moment of signing.