Full definition
Statutory maximum interest is the upper limit on interest for any monetary obligation under Polish law. Per Civil Code art. 359 §2¹, it equals twice the statutory interest rate (NBP reference rate + 3.5 p.p.) but no less than twice the NBP Lombard rate. In practice lenders observe the 2× Lombard cap. At the current Lombard rate of 5.75%, maximum capital interest is 11.5% per year. A separate cap exists for default interest (Civil Code art. 481 §2¹) = 2× statutory default interest ≈ 19.5%. Any excess is void — the consumer has the right to reclaim the overpayment.
Formula
Max interest = 2 × NBP Lombard rate (currently 2 × 5.75% = 11.5%).
Concrete numeric example
A 10,000 PLN loan over 12 months: capital interest cannot exceed 11.5% × 10,000 = 1,150 PLN/year. If the lender charges 15% (1,500 PLN), the consumer can reclaim 350 PLN — plus UOKiK may fine the lender.