You should be able to use your old Mexico SIM card again within 12 months of the time you last used it.. You have to register it showing ID (Passport usually for foreigners)
New activations can be done where you purchase it, otherwise online. Some people have had issues doing so.

Out of country roaming plans do not have to register. We have switched to a low cost carrier 'Public Mobile" a subsidiary of Telus and are paying Can$ 41 / month for 100 GB of data on a Can-USA- Mex plan. It ends up being more data and cheaper than paying for Telcel plan plus paying fee to hold our numbers back in Canada. Rogers now offers a comparable plan through a subsidiary. Both of these work in La Manzanilla.

Info copied from the internet is below this: Hope this is useful

You must register any local Mexican prepaid (pay-as-you-go) SIM card, as required by Mexico's Cell Phone Users Registration Program.

[1] (https://www.mexperience.com/all-mexico-cellphone-users-must-register/)

Key RequirementsMexicans and Legal Residents:
Must provide an official ID (INE or Mexican passport) and link their biometric CURP.

Tourists and Visitors:
Must present a valid passport during the activation process at the point of sale or via the carrier's digital portal.Contract/Postpaid Lines:

Exempt from the registration process for existing contract holders.Foreign Roaming / Travel eSIMs:
Foreign-issued numbers roaming in Mexico and international travel eSIMs do not need a Mexican registry.

[1] (https://www.mexperience.com/all-mexico-cellphone-users-must-register/),

[2] (https://www.facebook.com/huxwhatshappening/posts/important-mexico-now-requires-mobile-phone-numbers-to-be-registered-to-the-perso/1106883038330420/),

[3] (https://www.roafly.com/blog/mexico-sim-card-for-tourists),

[4] (https://nadanada.me/guides/destinations/mexico-esim-data-guide)

Deadlines and Disconnection:
The initial June deadline was replaced with a staggered disconnection timetable running between August and December 2026 based on the last digit of your phone number.



Unregistered lines face suspension for calls, texts, and data (emergency services remain active).


[1] (



[2] (https://www.mexperience.com/all-mexico-cellphone-users-must-register/)

How to RegisterOnline:
Visit your carrier's official website (such as Telcel's Line Linking Portal) to upload your ID and verify your details.

In Person:
Visit a carrier service center (Telcel, AT&T México, or Movistar) with your physical ID or passport