Mexico Is Disconnecting Unregistered SIM Cards Right Now

Since 15 August 2026, Mexico's phone carriers have been switching off prepaid lines that were never registered to a named person — the first wave hit numbers ending in 0, with the rest following in stages through 31 December 2026. If you're holding a Telcel or AT&T Mexico SIM you bought on a trip months ago and haven't touched since, there's a real chance it stops working mid-itinerary. If you're about to buy one at the airport, you'll be handing over a photo of your passport before the SIM activates at all.

What the rule actually says

Mexico's telecom regulator, the Comisión Reguladora de Telecomunicaciones (CRT), approved the "Lineamientos para la identificación de líneas telefónicas móviles" on 8 December 2025 and set them in motion on 9 January 2026. From that date, every mobile line in the country — prepaid or postpaid — has to be linked to an identified person or company: a voter credential or passport plus a CURP (Mexico's national population registry number) for individuals, or a tax ID for businesses. The stated goal is cutting down on phone-based fraud and extortion scams tied to anonymous SIMs, a problem Mexican carriers and regulators have flagged for years.

Postpaid contract lines were already tied to a billing identity, so the CRT quietly dropped the registration requirement for them. The pressure landed entirely on prepaid — the pay-as-you-go SIMs tourists actually buy.

Why the deadline moved, twice

The original cutoff was 30 June 2026. It didn't hold: Mexperience's July 2026 newsletter reported that by late June, less than half of all prepaid lines were registered, which is a lot of phones to cut off in one day. The government revised the plan into a staggered schedule instead of a single hard stop — disconnections now run 15 August through 31 December 2026, working through lines by their final digit. A disconnected line isn't cancelled outright; carriers reactivate it as soon as the owner completes registration, so the penalty is an inconvenience, not a lost number — but it's an inconvenience that can land while you're mid-trip and relying on that SIM for maps, rideshares, or hotel confirmations.

Does this apply to a tourist?

Yes, but only if you're buying a Mexican number. Mexperience's guide is explicit: "If you are a visitor or tourist to Mexico and purchase a local pre-pay SIM card (or eSIM) for use during your stay in the country, the registration that associates the number with your passport will be part of the activation process." In practice that means uploading a passport photo — and sometimes your device's IMEI — at the point of sale, whether you're doing it online through Telcel, AT&T, or Movistar, or in person at a carrier store. There's no fee for the registration itself.

The rule draws a clean line, though, around anything that isn't a Mexican-issued number: "If you roam in Mexico using a foreign-issued cell phone number, you do not need to register the number in Mexico." A phone connecting over international roaming — including a travel eSIM — never becomes a Mexican-registered line, so it sits outside the requirement entirely.

If you already have a local prepaid Mexican SIM from a past trip and plan to reuse it, register it before you fly rather than finding out at baggage claim that your line went quiet on 15 September or 15 October's disconnection wave.

The eSIM alternative

A travel eSIM built for Mexico, like Roameo's Mexico plans (49 plans currently listed, from $3.99), works by roaming onto local networks under a foreign-issued profile rather than being issued as a new Mexican number — the same architecture the CRT's own guidance exempts. That means no passport upload at activation, no CURP, and no risk of getting swept into a disconnection wave for a number you never meant to keep past the trip. You still get data the moment you land; you just never become a party to Mexico's national line registry in the first place. Check your device's eSIM support against Roameo's compatibility list before you fly, since not every phone sold outside Mexico carries an unlocked eSIM slot.

Mexico isn't alone in tightening this

The instinct to demand ID behind every SIM is spreading well beyond Mexico. Indonesia made facial-biometric verification mandatory for every new mobile number nationwide on 1 July 2026, after a five-month pilot that processed roughly 1.4 million registrations across Telkomsel, Indosat, and XL Smart with the ministry reporting no formal complaints. Vietnam, Thailand, and South Korea already run comparable systems. None of these rules touch a roaming line — they all target locally issued numbers — so the same logic that exempts a Mexico-bound traveler from RENAUT applies wherever a country tightens prepaid SIM identity checks: buy a local number and you register; roam on a foreign one and you don't.

What to actually do before you fly to Mexico

If you're planning to buy a physical Telcel or AT&T Mexico SIM at the airport, budget a few extra minutes for the passport-photo step at activation — it's part of the process now, not an optional add-on. If you'd rather skip carrier paperwork altogether, set up an eSIM before departure so it's already active and provisioned the moment you land, and keep a screenshot of your QR code or activation confirmation as backup in case you need to reinstall it. Either way, don't assume an old, unused Mexican prepaid SIM from a previous trip will still work — check it against the registration requirement before you rely on it.

An eSIM's real advantage here is timing, not just paperwork. Because installation happens over Wi-Fi, you can scan the QR code and let the profile download before you leave home — at the departure gate, or the night before — instead of standing in an arrivals hall trying to get a carrier's registration page to load on airport Wi-Fi. Most travel eSIMs sit installed but inactive until you land and the plan detects the local network, so there's no data burned by setting it up early. That also means no scramble to find a passport photo and hold still for it while a queue forms behind you at a phone kiosk — the entire process happens before departure, and the only thing you do on arrival is switch on data roaming.

FAQ

Will my Roameo Mexico eSIM get disconnected by this rule?

No. The RENAUT-style requirement applies to prepaid numbers issued by a Mexican carrier. A travel eSIM connects via international roaming on a foreign-issued profile, which Mexico's own guidance explicitly exempts from registration.

What happens if my Mexican prepaid SIM gets disconnected?

It isn't cancelled — carriers reactivate the line once you complete registration with a passport or voter ID plus CURP. But you'll lose service until you do, and the disconnection windows run in stages from 15 August through 31 December 2026 by the line's final digit.

Do I need to register if I'm only visiting Mexico for a week?

Only if you buy a local Mexican prepaid SIM or eSIM — registration happens automatically as part of activation, with a passport photo upload. If you use a foreign-issued roaming number instead, no registration is required.

Is there a fee to register a Mexican SIM?

No fee is charged for the registration itself, based on the carriers' published guidance — you provide ID documents (passport for visitors) and the carrier links them to the line.