y June 30, all mobile phone lines are supposed to be linked to the CURP (Mexico’s national identification number) of their owner. The government says the measure will help combat extortion, fraud, and anonymous criminal activity.

To register, users generally need to provide their name and CURP; companies use an RFC, while foreigners may register with a valid passport or temporary CURP.

But with the deadline approaching, questions remain about both compliance and effectiveness.

Recent reports suggest only about 49.5 million mobile lines have been registered so far, representing roughly 31% of Mexico’s estimated 161 million active lines. That leaves more than 114 million lines still unregistered.

Telecommunications operators and industry groups are questioning whether official figures accurately reflect what’s happening on the ground, particularly in Mexico’s massive prepaid market, which accounts for roughly 80% of all mobile lines. AT&T reported that only 17.3% of its prepaid customers had completed registration as of early May.

The current registry is Mexico’s third attempt at creating a national phone database.

In 2008, Mexico launched RENAUT, a registry intended to reduce extortion and other crimes. Instead, the database was compromised, and reports later alleged that records containing millions of phone numbers and personal details were being sold for as little as $500 USD. The program was eventually abandoned.

More recently, a biometric registry known as PANAUT was struck down by Mexico’s Supreme Court in 2022 over privacy concerns.

Digital rights organization R3D has long argued that phone registries create privacy risks while doing little to stop sophisticated criminals.

Those concerns gained new attention on January 9, the very first day registration began, when cybersecurity journalist Ignacio Gómez Villaseñor discovered a vulnerability in Telcel’s registration platform that exposed users’ names, birth dates, CURP numbers, RFC tax IDs, and email addresses.

According to security researchers, the information could be accessed simply by entering a phone number. The vulnerability was later patched, but only after the exposure had already been publicly documented.

Then, in late May, journalists documented active SIM cards being sold in Mexico City under other people’s identities for as little as 200 pesos — precisely the kind of loophole critics warned about from the start.

The current pushback extends beyond privacy advocates.

Telecommunications companies argue the program could cost operators more than 4 billion pesos while doing little to stop criminals who simply find ways around the system. Even Carlos Slim has questioned whether the registry will ultimately achieve its intended goals.

For now, the registry is moving forward. The government has repeatedly stated there will be no extension.

Beginning July 1, unregistered phone lines will be suspended. Users will lose the ability to make or receive calls, send text messages, or access mobile data until they complete the registration process. Lines left inactive for an extended period could eventually be canceled altogether.