Mexico Mobile Line Registration With CURP: Deadlines and Steps
Phone lines ending in 0 to 5 are past their deadline; 6 to 9 run through December. How foreign residents link a Telcel, AT&T or Movistar line, and what a suspension means.
Every mobile line from a Mexican carrier must be linked to its owner’s identity under rules issued by the federal Telecommunications Regulatory Commission (CRT). Mexicans use an official ID with their CURP; foreigners can use a CURP or a passport. Deadlines go by the last digit of the number, from August 15 to December 31, 2026, and unlinked lines are suspended within 72 hours of their date.
Who has to register a mobile line?
Everyone with a Mexican mobile number, prepaid or postpaid. The CRT approved the Guidelines for the Identification of Mobile Phone Lines (Lineamientos para la Identificación de Líneas Telefónicas Móviles) on December 8, 2025, and linking began on January 9, 2026. Under the guidelines, a new SIM sold through any channel can only receive emergency alerts and call emergency and customer service numbers until it is linked to a holder.
Companies and government bodies link their lines too, with the company’s RFC validated with the Tax Administration Service (SAT), and they must do it in person. Lines that cannot make calls, send SMS or use internet calling are excluded.
What are the deadlines by last digit?
After the original timetable, the CRT set a staggered calendar for 2026 by the last digit of the phone number:
| Last digit | Deadline (2026) | Status on November 5, 2026 |
|---|---|---|
| 0 | August 15 | Passed |
| 1 | August 31 | Passed |
| 2 | September 15 | Passed |
| 3 | September 30 | Passed |
| 4 | October 15 | Passed |
| 5 | October 31 | Passed |
| 6 | November 15 | Open |
| 7 | November 30 | Open |
| 8 | December 15 | Open |
| 9 | December 31 | Open |
The CRT said there would be no extension when the first deadline arrived. If your line ends in 0 to 5 and still works, link it anyway; carriers apply suspensions gradually.
What documents do foreign residents use?
The guidelines let foreigners register with a passport or a temporary CURP for foreigners. Residents who have a CURP can use it like a Mexican national, together with a valid official ID such as the resident card. For a foreigner, the carrier records only the name, country of origin, passport number or CURP, the phone number and the result of the identity check.
The guidelines bar carriers from storing biometric data, photos or copies of ID documents. One person can link up to 10 lines; people with a business activity can link more by showing a tax status certificate (constancia de situación fiscal).
How do you link a Telcel, AT&T or Movistar line?
- Open the CRT’s official portal, registratulinea.crt.gob.mx, which lists each carrier’s registration page and app.
- Follow the link for your carrier (Telcel, AT&T, Movistar or another company) and enter your phone number.
- Enter your CURP, or your passport details if you register as a foreigner without a CURP, and complete the identity check.
- Keep the confirmation, which carries a folio with the date and time.
- If online registration fails, go to a carrier customer service center (CAC) with your ID.
Use only the links on the CRT portal. Messages asking you to register through other websites or to send photos of your ID by chat are not part of the official process.
What about business lines and people with many phones?
Lines owned by companies and government bodies are linked in person at the carrier, with the company’s name and RFC, which the carrier validates with the SAT, plus the legal representative’s ID and proof of authority. Individuals can link up to 10 lines in their name. People with a business activity can exceed that by showing their tax status certificate, and holders who already had 10 or more postpaid lines when the guidelines took effect are exempt from the cap.
Every line counts toward the person it is linked to, so a parent who links the children’s phones uses part of that 10-line limit. Check every SIM in a tablet, router or car that uses a Mexican mobile number, since those lines can be suspended too.
What happens to a line that is not linked?
After the deadline, the carrier must warn you by SMS and then disable calls, text messages and mobile data within 72 hours. A suspended line keeps four functions: it receives earthquake alerts, it can call 911, it can call the citizen service numbers 079, 088 and 089, and it can contact the carrier. Our list of emergency numbers in Mexico City explains what each one does.
The line is not cancelled. Once you complete the link, service is restored right away, and the carriers’ registration platforms work without balance or mobile data.
Bottom line
Check the last digit of each line in your household, including children’s phones and spare SIMs, and link the ones ending in 6 to 9 before their dates. If a line is already suspended, link it from the carrier’s page on Wi-Fi to restore service.
FAQ
Do I need to register a US number roaming in Mexico?
The guidelines apply to mobile lines from Mexican carriers. A foreign SIM is not a Mexican line, so it is outside this registry; a Mexican SIM you buy on arrival must be linked before it works normally.
Where can I get help if linking fails?
The CRT takes questions about linking at [email protected] and general questions through the 079 line. Your carrier’s customer service center can also link the line in person.
Is my data stored with my ID photo?
No. The guidelines prohibit carriers from keeping biometric data, photos or copies of identification, and list only basic data plus a folio with the date and time.
