Bank margin (marża)

Definition. Bank margin is the fixed part of the loan rate that the bank adds to the interbank reference rate (WIBOR or WIRON). It is set at signing and does not change over the life of the loan (unless the contract says otherwise). On Polish mortgages in 2026 it sits between 1.8% and 3.0%.

A Polish mortgage rate has two parts: WIBOR 3M (or, from 2025, WIRON) plus the bank margin. WIBOR is variable — the NBP Council publishes it monthly — and it drives the swings in your monthly payment. The margin is fixed. If the bank wrote 2.4% into a 2020 contract, you pay it until 2050, regardless of the bank's condition, inflation, or a change of government.

The size of the margin depends on a few things. A 20%+ down payment usually shaves 0.3–0.5 pp. An active current account with the same lender: another 0.2–0.3 pp. Life insurance bought at the lender: another 0.1–0.2 pp. The 2026 Polish market floor: 1.8% at PKO BP with a 30% down payment, current account and insurance. Market standard: 2.4–2.8%.

Refinancing — moving the mortgage to another bank — pays off mostly when the new margin is at least 0.4 pp lower. Example: original margin 3.2%, refinancing to 2.5% on 25 remaining years and 400 000 PLN of principal saves about 70 000 PLN. But you have to count the switching cost: new valuation, bridging insurance, and the early-repayment fee at the old bank (up to 3% in the first 3 years).

Frequently asked questions

Can the margin change during the loan?+

In a standard mortgage contract — no. It only changes if the contract explicitly says so (for example, cancelling the lender's life insurance triggers a 0.3 pp rise).

What margin is normal on a cash loan?+

On a cash loan margin is rarely quoted — the nominal rate is used instead. Margin shows up mostly on mortgages, larger car loans and business credit.

When is mortgage refinancing worth it?+

When the new margin is at least 0.4 pp lower and you have 7–10+ years of the loan left. Anything shorter and the switching costs eat the saving.