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 power plan for storm season: battery bank, car charger, and offline maps

Step-by-step

1
Activate a US eSIM before you fly, or buy prepaid on landing
An eSIM bought before departure means you land with a working US number, which matters because banks, the DPS portal and rental applications all send SMS codes. No identity registration is required at any point in the US.
Mobile appWho: YouDay 1
2
Check your handset is unlocked and band-compatible
Handsets bought on contract abroad are frequently carrier-locked, and some regional models miss US band combinations. With 3G shut down there is no fallback network. Run your exact model through the carrier's compatibility tool.
OnlineWho: You
3
Start prepaid rather than fighting a credit check
Postpaid runs a credit check and a newcomer with no file is declined or asked for a deposit of several hundred dollars. Prepaid has no check, no contract, and is usually cheaper for the same data on the same network.
OnlineWho: You
4
Sign up for ReadyHarris and the local alert systems
Harris County's emergency notification system sends evacuation, flooding and boil-water alerts to your phone, and it is opt-in — it will not find you automatically. Add Houston TranStar's flood-warning map and the National Weather Service alerts at the same time. This is a ten-minute task that matters once a year and matters enormously.
OnlineWho: YouWeek 1
5
Prepare for multi-day outages before the season starts
The May 2024 derecho and Hurricane Beryl both knocked out power to large parts of the metro for over a week. A large battery bank, a car charging cable and downloaded offline maps are the practical minimum. Text messages get through when calls and data do not, so tell family abroad to expect texts rather than video calls.
Mobile appWho: You
6
Get home internet by exact address, and expect fibre in newer areas
AT&T Fiber and Comcast cover most of the metro, with fibre availability strongest in the newer master-planned suburbs and patchier in older inner-Loop blocks. Check the specific address rather than the neighbourhood, and ask what happened to service at that building in the 2024 storms.
OnlineWho: You

Documents you’ll need

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

Things most newcomers don’t know

The phone is the emergency system here, and the network fails with the grid.

After Beryl and the 2024 derecho, mobile sites across the metro ran out of backup power within a day or two while households were still without electricity. SMS often survives when voice and data do not, because it needs far less bandwidth. Agree in advance with people abroad that a text means 'we are fine' — otherwise a week of silence reads as a catastrophe.

Source: community-reported

County emergency alerts are opt-in and will not find you.

ReadyHarris and the equivalent systems in Fort Bend and Montgomery counties send evacuation orders, flood warnings and boil-water notices, but you have to register your address and number. Newcomers assume US emergency alerts are automatic because presidential-level wireless alerts are. The local ones — the ones that tell you your specific street is being evacuated — are not.

Source: Harris County Office of Homeland Security & Emergency Management

The US has no SIM registration of any kind.

Most countries in this app require passport registration to activate a SIM and several require biometrics on top. The US requires nothing at all for prepaid — you can buy one with cash and never give a name. Arriving from the Gulf, Nigeria or South Asia the absence of paperwork reads like an oversight. It is deliberate.

Source: community-reported

The credit check is the barrier to postpaid, not the paperwork.

Carriers screen credit before offering a postpaid plan, and a newcomer with no file is declined or charged a deposit of a few hundred dollars. Nobody at the counter explains that prepaid avoids the check entirely, runs on the same towers, costs less, and can convert to postpaid later once you have history.

Source: community-reported

Common mistakes to avoid

Never registering for ReadyHarris and missing an evacuation notice for your own street.
Assuming mobile networks stay up during a multi-day power outage.
Bringing a carrier-locked handset and discovering it after landing.
Applying for postpaid with no credit file and facing a large deposit.
Relying on a foreign number for bank, DPS and rental-application SMS verification.

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