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

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. Otherwise carrier stores, the airport and big-box retailers sell prepaid SIMs. No identity registration is required at any point.
OnlineWho: YouDay 1
2
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. Check the carrier's compatibility tool against your exact model.
OnlineWho: You
3
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 of a few hundred dollars. Prepaid has no check, no contract and is usually cheaper for the same data.
OnlineWho: You
4
Consider an MVNO on the same towers
Mint Mobile, Visible, US Mobile and Google Fi resell capacity on AT&T, T-Mobile and Verizon. Same coverage, materially lower price; the trade is deprioritised data during congestion and thinner support.
Mobile appWho: You
5
Set up emergency alerts and a hurricane plan for your phone
Wireless Emergency Alerts are on by default and will warn you of evacuation orders — do not switch them off. Keep a power bank charged through the season, and note that after a major storm networks can be down for days regardless of carrier.
Mobile appWho: YouBefore 1 June
6
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, which releases the number permanently.
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

The US has no SIM registration at all.

Most countries in this app require passport registration to activate a SIM and several require biometrics. The US requires nothing for prepaid. Arriving from Latin America, the Gulf or South Asia, the absence of paperwork is genuinely surprising.

Source: community-reported

Hurricane resilience is a real differentiator between carriers here.

After major storms, network restoration times vary substantially by carrier and by neighbourhood, depending on tower hardening and backup power. This is a consideration in South Florida that simply does not arise in most US cities — worth asking locally which network held up in the last big storm.

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 and usually costs less, so the workaround is also the better deal.

Source: community-reported

MVNOs use the same towers for meaningfully less.

Mint, Visible, US Mobile and Google Fi lease capacity from the big three. Coverage is identical; you give up priority during congestion and retail support. For a single line the saving is large and the compromise small.

Source: community-reported

Common mistakes to avoid

Bringing a carrier-locked handset and discovering it on arrival.
Applying for postpaid with no credit file and facing a large deposit.
Turning off Wireless Emergency Alerts because they are loud — they carry evacuation orders.
Cancelling the old carrier before requesting the port, and losing the number.
Relying on a foreign number for bank and government SMS verification.

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