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 for rides, deliveries and bank verification codes. 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 network to land on.
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. Prepaid has no check and is usually cheaper for the same data allowance.
OnlineWho: You
4
Check fibre at the exact address before you sign the lease
Louisville's fibre build is uneven street by street — a block in Germantown may be cable-only while the next one over has fibre, and the newer eastern subdivisions are better served than the older core. For anyone working remotely this is a bigger practical decision than the mobile carrier. Use the FCC broadband map on the specific address.
OnlineWho: YouBefore signing a lease
5
Test coverage indoors in the actual flat
Older brick and the river-valley terrain both matter here, and carriers differ noticeably indoors. If you can, stand in the room you would work in with a friend's phone on a different network before signing a 24-month device agreement. Wi-Fi calling closes most of the gap and is worth enabling regardless.
In personWho: You
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, 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

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. The US requires nothing whatsoever for prepaid — you can buy one in a supermarket and be online in minutes.

Source: FCC — consumer guides

Check home internet at the exact address, not the neighbourhood.

Louisville's fibre coverage is uneven street by street, and a block in the older core can be served by cable only while the next one has fibre. For a remote worker it is a bigger practical decision than the mobile carrier, and it is worth checking before signing the lease rather than after.

Source: FCC — National Broadband Map

Device financing survives cancelling the plan.

A phone bought on a carrier instalment plan stays owed even if you leave, and leaving early can accelerate the balance. If your stay is uncertain, buy the handset outright and use a cheap prepaid plan.

Source: FCC — consumer guides