Before you start

An unlocked or eSIM-capable handset
Passport for SIM registration
PESEL, a Polish address and a bank account for a postpaid contract
Landlord or building administrator consent for a fixed-line installation

Step-by-step

1
Buy and register a prepaid SIM
Operator shops, kiosks and supermarkets sell them and registration against your passport happens at the counter. An unregistered SIM is deactivated within days.
In personWho: YouPLN 5–30 including starter credit
2
Use EU roaming while you compare
Arriving from another EU country, your existing SIM works at home rates. There is no reason to buy at the airport.
OnlineWho: You
3
Turn off data roaming before boarding a ferry
The Gdynia–Karlskrona route and cruise vessels use satellite-backed maritime networks charged at rates outside the EU roaming cap. A few hours of background sync produces a genuinely alarming bill.
Mobile appWho: You
4
Ask the building, not the postcode, about fibre
New developments and postwar blocks are well served. In the prewar tenements of Wrzeszcz, Oliwa and Śródmieście, ask the administrator which operators are physically wired in before you sign.
In personWho: YouBefore signing a lease
5
Order installation the week you sign
Where fibre exists, installation runs one to three weeks and often needs the administrator's consent for new cabling. Starting it at the lease signing rather than the move-in saves a fortnight of tethering.
OnlineWho: You
6
Move to postpaid once settled
Contracts want PESEL, a Polish address and a bank account for direct debit. Prepaid pricing is good enough that many residents never switch.
In personWho: You

Documents you’ll need

Passport for SIM registration
PESEL and Polish bank account, for postpaid
Lease or written landlord consent, for a fixed-line installation
Proof of address, for some contracts

Things most newcomers don’t know

Maritime networks on the Baltic ferries are outside EU roaming rules.

Roam-like-at-home applies to terrestrial networks in EU member states. Ships use satellite-backed maritime operators that fall outside it entirely, and a phone will latch onto one silently once the coast drops away. The Gdynia–Karlskrona crossing is a popular weekend from here, and the standard outcome is a three-figure bill for background app traffic. Turn data roaming off at the terminal, not on the deck.

Source: EU roaming regulation — maritime and aircraft networks excluded

Anonymous prepaid does not exist in Poland.

Every SIM, prepaid included, must be registered to an identified person under Polish telecommunications law. There is no cash-and-go option and a SIM sold without proper registration stops working. Bring your passport to the kiosk rather than expecting to register later online.

Source: Polish telecommunications law

Fibre availability tracks the building's age and renovation, not the district.

Gdańsk's postwar estates in Przymorze and Zaspa and the new riverside developments are comprehensively fibred. The prewar tenement stock in Wrzeszcz, Oliwa and the rebuilt Śródmieście is uneven, and operator coverage checkers answer at street level. The administrator of the building knows the real answer and will tell you if you ask before signing.

Source: community-reported

Polish mobile data is cheap enough that a router is a real alternative.

Unlimited or high-cap 5G plans cost a fraction of Western European equivalents and Tricity coverage along the rail corridor is dense. For one person in a building where fibre is uncertain, a mobile router is a legitimate permanent connection rather than a stopgap, and it removes any dependency on a landlord and an engineer cooperating.

Source: community-reported

Common mistakes to avoid

Leaving data roaming on for a Baltic ferry crossing.
Expecting to buy an unregistered prepaid SIM.
Trusting a street-level coverage checker for a prewar Wrzeszcz tenement.
Cancelling an old contract before starting the number port, which releases the number.
Signing a 24-month contract before you have PESEL and a Polish bank account.

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