When refi adds up mathematically
Rule of thumb: the RRSO gap between old and new should be at least 3 percentage points and the remaining term at least 24 months. Below that gap, operation costs eat the saving. Below that horizon, a lower instalment doesn't have time to sum up to a real number.
Fees to subtract from savings
The new bank charges 1-3% commission on the refinanced amount. The old bank may charge an early-repayment fee (up to 3% of the outstanding amount in the first 36 months of the loan). Notary fees on a mortgage or bridging insurance add 500-1 500 PLN. These costs need to enter the savings math.
Specific refinancing offers
Alior Bank refinances cash and consolidation loans up to 200 000 PLN, RRSO from 12.5%, commission 1.99%. mBank refinances when at least 12 months remain on the term, RRSO from 14%. Santander Consumer Bank specialises in refinancing expensive instalment loans, RRSO from 11.8%. ING accepts refinancing only from its own clients (account with ING for at least 6 months).
Mortgage refi runs on a different ledger
A refinanced mortgage carries more costs: notary fee (1 500-3 000 PLN), court fee for the new mortgage (200 PLN), bridging insurance (0.5-1% of principal per year until the new mortgage is entered). Mortgage refi starts to pay off at a 1.5-2 point RRSO gap and at least 8-10 years left on the term. With less time on the clock, even a 2-point gap doesn't cover the operation.
My take: when to skip it
If less than 24 months of cash-loan repayment remain, skip refi. If the RRSO gap is under 3 points, skip. If the old bank takes the maximum early-repayment fee (3%), usually skip. Refi works best for fresh, large loans at a high rate, a context you usually remember because you took it in a tight moment.