TLK (Poland)

Twoje Linie Kolejowe (TLK) services were introduced by Polish express train operator PKP, to provide a lower cost alternative than travelling long distance on the EIP, the EIC or the IC services.

Low cost means a more basic level of on-board service, few TLK services convey any form of catering and PKP also tends to use its oldest trains for TLK services.

On most routes taken by the faster EIP and EIC trains, these TLK services are indeed a lower cost, more basic, but slower* alternative, to taking those trains.
*Check the journey times carefully if travelling for the cheapest possible price matters more to you than the on-board experience - the TLK services can be less than 30mins slower than the EIP and EIC services.

But when TLK services share a route with IC services, the distinction between the two services can be more blurred.
The TLK services can be faster, but cheaper - and the on-board experiences may not be markedly different either.

The routes that TLK and IC services share include:
(1) Warszawa - Torun - Bydgoszcz
(2) Warszawa - Bialystock
(3) Warszawa - Lublin
(4) Poznan - Wroclaw - Katowice - Krakow - Rzeszow - Przemysl

All tickets for TLK trains are seat specific, seat reservations are complimentary and included with the booking, so when you arrive on the peron/platform, check the coach number that you will printed on your ticket.

Something to be aware of is that the trains can’t be boarded until the destination details etc are displayed on the electronic indicators.

At the stations where a TLK train will be commencing its journey - the train may be waiting with doors open, it will be fairly obvious that it is the train you will be taking and you have a reserved seat.
However, the train may still being prepared for service, and if you board too soon, the conductor will politely ask you to leave.

If you will be travelling with a rail pass you MUST reserve a seat(s) prior to boarding these trains - but if you book the reservation at a station in Poland, you won't be charged for it.
Therefore ideally do this when you first arrive at a station in Poland and not just before you board your chosen departure.

However, as there's now also no charge for a rail pass reservations on EIC services, if there are faster EIC services on the route you wish to take, it makes sense to target those departures instead.
Also if you are going to travelling on a route taken by the EIP trains, consider whether it's worth paying the fee to have a much faster and more comfortable journey by those trains.

For these reasons it can be a good idea to look up your journey on the PKP website, even though you won't be purchasing a ticket.