Before you start

An unlocked phone (nearly all carriers run on Telcel/AT&T/Altan bands, so US, EU and Asian phones generally work)
A passport or, once you are a resident, your green resident card - needed both to buy and to register the line
A CURP (the 18-character population ID) to register the line - residents get one automatically; tourists can pull a free Temporary CURP from the RENAPO site
Cash or a card; an OXXO is on almost every corner for buying SIMs and topping up

Step-by-step

1
Pick prepago (Amigo) vs a plan (postpago)
Start with prepago: no contract, no credit check, no proof of address - ideal before you have a CURP or a Mexican address. Telcel Amigo gives the widest coverage; Bait (Walmart's MVNO on the Altan network) and weex are the cheapest. Switch to a postpago plan later for more GB per peso once you have residency and a local address. Note Bait rides Altan, not Telcel, so its rural coverage differs.
In personWho: Everyone choosing a line typePrepago SIM about MXN 50-150; eSIM similar
2
Buy the SIM or activate an eSIM
Physical SIMs are sold at OXXO, Walmart/Bodega Aurrera, supermarket counters, carrier stores (CACs) and airport kiosks. Telcel sells prepago eSIM fully online via the Mi Telcel app or telcel.com - no store visit - by buying any Paquete Amigo Sin Limite; Bait and Movistar also do prepago eSIM 100% digitally. Check your phone shows eSIM support before relying on it.
In personWho: All new users10-20 minutes in store; minutes for an eSIMFree SIM with some recharges; otherwise MXN 50-150
3
Register the line to your CURP + ID (mandatory since Jan 2026)
Link the number to your CURP and a valid ID (passport, INE, or your resident card). Telcel does this at telcel.com/vinculatulinea, in Mi Telcel, or at any CAC; other carriers have equivalent portals. Existing lines must be registered before service is cut - carriers began suspending unregistered lines around the end of June 2026. Up to 10 lines may be tied to one CURP. No biometrics are collected.
OnlineWho: Every line holder (prepago and postpago)Same day onlineFree
4
Recharge prepago or set up plan billing
For Amigo, buy a Paquete Amigo Sin Limite (data + unlimited social apps + calls/SMS to MX, US and Canada) at OXXO, in Mi Telcel, online, or by dialing *133#. Recharge amounts run MXN 20-500; a typical 30-day package is around MXN 200. Check balance and expiry anytime free with *133#. For a postpago plan you pass a credit check and set up a card or bank auto-pay.
Mobile appWho: Prepago top-ups and plan subscribersInstantAmigo packages from ~MXN 50; ~MXN 200 for a 30-day bundle

Documents you’ll need

Passport (to buy and register before you have a resident card)
CURP - printed on the resident card, or a free Temporary CURP from RENAPO for non-residents
Valid photo ID for registration: passport, INE credential, or green resident card
For a postpago plan: proof of Mexican address (CFE bill or bank statement) and often a Mexican debit/credit card for auto-pay

Things most newcomers don’t know

The scary biometric SIM registry never came back - but a CURP-based one did. The Supreme Court killed the biometric PANAUT (no fingerprints/iris), yet a separate non-biometric rule from January 2026 still ties every line, prepaid included, to your CURP and ID.

Expats often arrive thinking Mexican prepaid is fully anonymous (true pre-2026) or fear handing over biometrics (not required). Reality is the middle: ID + CURP, no biometrics.

Source: CRT/IFT Lineamientos; SCJN Accion 82/2021

Telcel is the default for a reason: the broadest coverage in the country, especially outside big cities, so it is the safe pick if you travel around Mexico.

MVNOs like Bait are cheaper but ride other networks (Bait uses Altan), so coverage and speeds can drop in less-dense areas where Telcel still reaches.

Source: IFT/CRT cobertura movil data

Go prepago first, postpago later. A plan needs a credit history, a Mexican address and often a local card - things a brand-new arrival lacks - whereas Amigo needs none of that, just the CURP registration.

Carriers run credit checks for postpago; newcomers usually fail them in the first months, so prepago bridges the gap until residency and banking are sorted.

Source: Carrier postpago requirements

Memorize *133# - the free Telcel Amigo command for checking balance, data left and expiry, and buying packages, even with no data connection.

Avoids surprise cut-offs; works offline via USSD, unlike the app, and never costs credit to use.

Source: Telcel Amigo

Common mistakes to avoid

Letting prepago credit lapse - if you stop recharging, the number can be recycled and you lose it; keep a small recharge active between trips.
Skipping the CURP line-registration: unregistered lines (including prepaid) started getting suspended around the end of June 2026, and a dead SIM cannot receive your bank/2FA codes.
Tourists assuming they cannot register because they lack a CURP - you can pull a free Temporary CURP from RENAPO with your passport; you do not need residency for that.
Buying a locked phone abroad or assuming any SIM works - confirm your handset is unlocked and band-compatible, and verify eSIM support before choosing eSIM over a physical SIM.

Make it your personal checklist

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