Unregistered Mobile Lines Could Block Access to Digital Banking in Mexico

Mexico City — Mobile phone users in Mexico who fail to register their lines with their carriers risk losing access to digital banking services, as banks tighten security protocols linked to phone numbers.

The restriction comes at a time when mobile banking is surging. A BBVA Mexico study estimates that 18.9% of all banking transactions in the country were conducted via mobile devices in 2025, with that figure projected to reach 23.1% by 2030.

When a mobile number changes, banks such as BBVA Mexico and Santander typically require customers to visit a branch in person with official identification and the device to update their records. The same process applies if a line is not registered with the carrier.

“In this case, it would be necessary to go directly to a branch to change the phone number and access channel,” a BBVA customer service representative said.

Santander similarly requires updating contact details because the system sends critical information to the “trusted phone” — the previous number.

To date, approximately 57 million mobile phone users have registered their lines out of more than 160 million total, leaving a large gap. Carriers like AT&T are promoting registration through programs such as “Cuidado Digital.”

Radames Camargo, an analyst at The Competitive Intelligence Unit (CIU), warned of “effects not only sectoral but transversal, and the economic paralysis that registration could cause” if authorities do not consider its broader implications. He noted that the measure could overwhelm bank branches as users flock to update their numbers.

Camargo also pointed to Banxico’s Dimo payment system, which relies on phone numbers for transactions, raising questions about service continuity if lines are suspended.

The impact extends beyond banking. Two-factor authentication for many digital services — including e-commerce and delivery apps — depends on SMS verification codes sent to mobile phones. If lines are suspended starting July 1 due to lack of registration, users may lose access to these services or face security vulnerabilities.

“If a line is suspended from July 1 due to lack of registration, it will be necessary to resort to other two-factor authentication methods, whose ability to replace the phone line is uncertain,” Camargo warned.