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
Wireless Emergency Alerts left switched on

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 DMV 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 towers.
OnlineWho: You
4
Leave Wireless Emergency Alerts on, including earthquake warnings
California's earthquake early warning system delivers seconds of notice before shaking arrives, through the same federal alert channel as AMBER and weather warnings. Seconds are enough to get away from glass and under a table. The MyShake app adds a second, more sensitive channel. Newcomers often disable alerts after a false alarm and then have no warning at all.
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5
Get home internet by exact address before you sign the lease
Availability in Long Beach is address-specific and the difference between fibre and older cable is large — the newer downtown and Douglas Park buildings are well served while parts of the older central and west-side stock are not. Check the FCC broadband map and the providers' own address lookups if you work from home.
OnlineWho: You
6
Expect patchy coverage in the harbour and on the water
Signal on the beach and in most of the city is fine. Out on Alamitos Bay, on the Catalina ferry or deep inside the port's terminal areas it is not, and the Catalina crossing is a common day out here. Download what you need before you get on the boat.
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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 1933 Long Beach earthquake is why every Californian school building is built the way it is.

The magnitude 6.4 quake on 10 March 1933 destroyed or badly damaged scores of school buildings in this city. Within a month the legislature passed the Field Act, putting school construction under the Division of the State Architect with mandatory seismic review — a regime that still governs every public school in California and is the reason schools are the designated refuge in a quake. The Riley Act followed for other buildings. Long Beach is where the whole state's seismic building code starts.

Source: California Division of the State Architect

Earthquake early warning arrives through the same channel as AMBER alerts.

California's ShakeAlert-powered warnings are pushed as Wireless Emergency Alerts, so switching off the category that woke you at 3am also switches off the one that would give you ten seconds before shaking. Keep them on and install MyShake as a second channel. The warning is short by design — it is time to get away from windows, not time to leave the building.

Source: California Governor's Office of Emergency Services

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. The US requires nothing at all for prepaid — you can buy one with cash and never give a name. Arriving from Mexico, the Philippines or India, the total 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 converts to postpaid later once you have history.

Source: community-reported

Common mistakes to avoid

Switching off Wireless Emergency Alerts and losing earthquake early warning with them.
Signing a lease for a work-from-home flat without checking what broadband actually reaches the address.
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 and DMV SMS verification.

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