Full definition
A term deposit is the safest way to grow savings in Poland — the bank commits to return principal plus interest at a contractual rate after a fixed period. Unlike a savings account, the rate on a term deposit is fixed for the whole term (except for progressive or variable deposits). Funds are BFG-guaranteed up to EUR 100,000 per person per bank. Interest is subject to 19% Belka tax, withheld automatically by the bank. Compounding can be monthly, quarterly, annual or at the end of the term — more frequent compounding = higher effective yield. Popular formats: standard (fixed rate throughout), "new-money" deposit (only for fresh funds, often the highest promo rate), progressive (rate rises each period), structured (principal-guaranteed with an upside based on an underlying — you might receive only principal).
Concrete numeric example
A 50,000 PLN 12-month deposit at 6%, annual compounding. Gross interest: 3,000 PLN. Belka tax 19%: 570 PLN. Net payout: 52,430 PLN. Effective net return: 4.86%.