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 all 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 decide
If you arrive from another EU country your existing SIM works at home rates under roam-like-at-home. There is no urgency and no reason to buy at the airport.
OnlineWho: You
3
Ask the building, not the coverage map
In Śródmieście, Bałuty and along Piotrkowska, ask the landlord or administrator which operators are physically wired into the stairwell. A revitalised kamienica often has full fibre; the unrenovated one next door may have copper or nothing.
In personWho: YouBefore signing a lease
4
Order the installation early
Where fibre exists, installation runs one to three weeks and usually needs an engineer plus the administrator's permission for any new cabling. Start it the week you sign, not the week you move.
OnlineWho: You
5
Keep a mobile router as the fallback
5G coverage across Łódź is good and unlimited-data plans are cheap. If your building turns out to be a copper one, a router on a mobile plan is a legitimate permanent answer rather than a stopgap.
OnlineWho: 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

Łódź's internet quality tracks the revitalisation programme, not the postcode.

The city has spent a decade rebuilding the nineteenth-century centre block by block with EU funding, and the programme moved street by street rather than district by district. Two tenements on the same stretch of Włókiennicza or Legionów can differ between symmetric fibre and ageing copper because one was in a completed area and one was not. Operator checkers answer at street level and therefore answer the wrong question.

Source: community-reported

There is no anonymous prepaid market in Poland.

Polish telecommunications law requires every SIM, prepaid included, to be registered to an identified person. There is no way to buy one for cash without documents, and one sold without proper registration is deactivated. Bring a passport to the kiosk instead of expecting to sort it out later.

Source: Polish telecommunications law

Polish mobile pricing makes fixed-line genuinely optional for one person.

Unlimited or high-cap 5G plans here cost a fraction of what equivalent plans cost in Western Europe. For a single-occupancy flat that is a real substitute rather than a compromise, and it removes any dependency on a landlord, an administrator and an engineer all cooperating in the same month — which in an unrenovated Łódź tenement is a genuine risk.

Source: community-reported, consistent with EU price comparisons

Port the number from the new operator; never cancel the old contract first.

Polish number portability is quick and free, but it only works while the outgoing contract is live. Terminating first releases the number and it is no longer yours to move. Start the process at the new operator, who then handles the termination as part of the transfer.

Source: UKE — Office of Electronic Communications