Even within mentioned life style there are dozen of possibilities so you must assume that below calculations may vary even up to 50% based on real situation.
However, you may expect (for Katowice and nearby cities and for single person):
Basic monthly costs:
- 1000 PLN (225 EUR) for food, assuming your own preparation mostly,
- from 1000 PLN (225 EUR) for single-room flat to 2000 PLN (450 EUR) for triple-room flat,
- 100-200 PLN (25-45 EUR) for standard, single-person private medical insurance,
- 200 PLN (45 EUR) for monthly bus/tram ticket (trains not included, no metro here).
Notice, that we use total room count, not bedroom count, in flat rent business. Single room flat ("kawalerka" in Polish) means that you eat, sleep and live in the very same room. You have a kitchen (either full or kitchen annex in that room) and bathroom, but you have a single room at all. It does not mean single bedroom plus any kind of living room as this counts as two-room flat in Poland.
Other example expenses:
- 5+ PLN (1+ EUR) beer, 15+ PLN (3.5+ EUR) drink or 20 cigarettes,
- around 50-70 PLN (14 EUR) for lunch or diner at a restaurant,
- 25-30 PLN (6 EUR) for single cinema ticket,
- 300 PLN (70 EUR) for fuel for single-person used car just to get to work and back (car hire itself not included, as this is a whole different story -- look on Polish subsites of car hire websites).
To put together, we have: 1000 PLN (food) + 1500 PLN (medium flat rent) + 200 PLN (bus/tram ticket) + 200 PLN (medical insurance) ~= 3000 PLN (675 EUR) per month - 36000 PLN (8100 EUR) for a year as a complete minimum to live here (with extra costs and/or a bit better lifestyle not included).
- PLN-to-EUR calculation assumes today's medium exchange rate of 1 PLN = 0.23 EUR.
- Katowice / Southern Poland is not that expensive in compare to other parts of Poland. More famous cities (like capital Warsaw, Cracow, Wrocław, Poznań, Łodż, Gdańsk etc.) are by far more expensive.