Tips in Polish restaurants are a matter of habit rather than obligation.
In Poland, a tip is not habitually included in the bill.
However, satisfied customers usually leave an extra amount of 10–15% of the bill in restaurants, bars and clubs where waiters and waitresses serve guests.
In pubs and clubs where guests come to the counter, there are money boxes into which you can throw a voluntary donation. It is also a form of acknowledgement and non-obligatory gratification.