Before you start

An unlocked handset, or an eSIM-capable one
A US address for postpaid, but not for prepaid
A payment method — prepaid accepts foreign cards, postpaid usually does not
A plan that either includes Mexico or a handset set not to roam onto it

Step-by-step

1
Activate an eSIM before flying, or buy prepaid on arrival
A US eSIM activates before you land so you have a working number immediately for rides, deliveries and bank verification codes. No identity registration is required at any point.
OnlineWho: YouDay 1
2
Check whether your plan covers Mexico before you sign it
In much of southern and eastern El Paso your phone can see Juárez towers more clearly than US ones. Plans that include Mexico make this a non-event; plans that do not can bill it as international roaming while you are standing in your own kitchen. Ask the question explicitly at the counter — it is the single most useful telecom question in this city.
OnlineWho: YouBefore choosing a plan
3
Turn off international data roaming if your plan excludes Mexico
On both iOS and Android the setting is per-line and easy to find. Doing it on day one costs nothing and prevents the classic first-month El Paso phone bill.
Mobile appWho: YouDay 1
4
Check your handset is unlocked and band-compatible
Phones bought on contract abroad are frequently locked, and US band combinations trip up some regional models. With 3G shut down there is no fallback network to land on.
OnlineWho: You
5
Start prepaid rather than fighting a credit check
Postpaid runs a credit check. With no US file you will be declined or asked for a deposit. Prepaid has no check and is usually cheaper for the same data allowance.
OnlineWho: You
6
Leave emergency alerts switched on
Flash flood warnings during the monsoon, dust storm warnings in spring and extreme heat warnings in summer all arrive through the federal wireless alert system. The flood ones in particular matter here, because the arroyos fill faster than the roads close.
Mobile appWho: YouWeek 1
7
Shop home internet by address
Coverage varies sharply between the older central and Lower Valley neighbourhoods and the newer far east and far west developments. Check the FCC's map for the specific address rather than the neighbourhood before signing a 12-month term.
OnlineWho: You
8
Port rather than cancel if you switch later
Number portability is a legal right and works between carriers and MVNOs. Request the port from the new carrier — never cancel the old service first, or you lose the number.
OnlineWho: You

Documents you’ll need

Passport for postpaid; nothing at all for prepaid
US address for postpaid
A payment card — prepaid usually accepts foreign cards, postpaid rarely does

Things most newcomers don’t know

Your phone will try to roam onto Mexico from inside your own house.

Juárez sits immediately across the river and its cell sites cover a great deal of southern and eastern El Paso. Handsets pick the strongest signal, not the correct country. On a plan that includes Mexico this is invisible; on one that does not, it produces an international roaming bill generated entirely within the United States. Ask about Mexico coverage before you pick the plan.

Source: community-reported

The credit check is the barrier, not the documentation.

Carriers check credit before offering postpaid, and a newcomer with no file gets declined or charged a deposit. Prepaid sidesteps it entirely and usually costs less for the same data.

Source: community-reported

The US has no SIM registration at all.

Most countries in this app require passport registration to activate a SIM — Mexico included. The US requires nothing whatsoever for prepaid. If you are used to registering a SIM against a passport, the absence of any process here is disconcerting and entirely normal.

Source: FCC — consumer guides

Flood alerts are the ones not to silence, in a desert.

El Paso gets very little rain and most of it arrives between July and September in short violent storms. Arroyos and underpasses fill in minutes and the wireless emergency alert is frequently the first warning. People silence alerts after a loud test in a place where it rains twenty days a year, which is exactly backwards.

Source: FCC — Wireless Emergency Alerts

Common mistakes to avoid

Choosing a plan without checking whether Mexico is included, then roaming at home.
Applying for postpaid with no credit file and facing a large deposit.
Bringing a carrier-locked handset from abroad and discovering it on arrival.
Silencing flood alerts because it is a desert. It floods anyway.
Cancelling the old carrier before requesting the port, and losing the number.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.