Polish mortgage overpayment calculator
On a 300,000 zł loan over 25 years at 6.5%, a one-off overpayment of 50,000 zł shortens repayment by almost 8 years and saves about 142,000 zł in interest. In “lower the payment” mode the same overpayment cuts the instalment from 2,026 zł to 1,688 zł. Enter the loan amount, rate and planned overpayment.
Overpayment type
Overpayment effect
Interest saved: PLN 124,973
Time cut by (years / months): 7 / 6 mo
| Comparison | Without overpayment | With overpayment |
|---|---|---|
| Payoff time (years / months) | 25 / 0 mo | 17 / 6 mo |
| Total interest | PLN 278,220 | PLN 153,248 |
Schedule with overpayment
| Year | Interest | Principal | Balance |
|---|---|---|---|
| 1 | PLN 14,959 | PLN 58,169 | PLN 241,831 |
| 2 | PLN 14,195 | PLN 8,933 | PLN 232,897 |
| 3 | PLN 13,647 | PLN 9,482 | PLN 223,415 |
| 4 | PLN 13,065 | PLN 10,063 | PLN 213,352 |
| 5 | PLN 12,448 | PLN 10,681 | PLN 202,671 |
| 6 | PLN 11,793 | PLN 11,336 | PLN 191,335 |
| 7 | PLN 11,097 | PLN 12,032 | PLN 179,303 |
| 8 | PLN 10,359 | PLN 12,770 | PLN 166,533 |
| 9 | PLN 9,575 | PLN 13,554 | PLN 152,979 |
| 10 | PLN 8,743 | PLN 14,385 | PLN 138,593 |
| … | |||
| 18 | PLN 154 | PLN 9,902 | PLN 0 |
This calculation is indicative and assumes a constant rate over the whole term and the full overpayment applied to principal. It ignores early-repayment fees and rate changes. Confirm the overpayment terms in your loan agreement.
How mortgage overpayment works in Poland
An overpayment is any amount paid on top of the required instalment. The bank applies it in full to the principal, so from the next month interest is charged on a lower balance. The earlier in the term you overpay, the larger the saving.
An overpayment can be handled two ways: shorten the term (the instalment stays the same and the loan clears sooner – the biggest interest saving) or lower the payment (the term stays and the bank recalculates the instalment downwards – a smaller saving but lighter monthly load).
Under the Polish mortgage credit act, overpaying a housing loan is allowed at any time. An early-repayment fee may only be charged in the first 3 years and only on a variable rate – no more than 3% of the amount overpaid and no more than one year's interest.
Examples: one-off overpayment → interest saved (400,000 zł, 25 years, shorten the term)
| One-off overpayment | Interest saved |
|---|---|
| PLN 10,000 | PLN 32,420 |
| PLN 20,000 | PLN 61,629 |
| PLN 50,000 | PLN 134,074 |
| PLN 100,000 | PLN 219,599 |
| PLN 150,000 | PLN 276,914 |
| PLN 200,000 | PLN 315,760 |
FAQ
Which is better – shortening the term or lowering the payment?
Shortening the term while keeping the instalment gives the biggest interest saving. Lowering the payment eases the monthly budget, but the total cost of the loan falls much less.
Can the bank charge a fee for overpaying?
Only in the first 3 years and only on a variable rate – at most 3% of the amount and no more than one year's interest. After 3 years, overpaying a housing loan is free.
How much do I save by overpaying 50,000 zł?
On a 300,000 zł loan at 6.5% over 25 years, a one-off overpayment of 50,000 zł shortens repayment by about 95 months and saves roughly 142,000 zł in interest (shorten-the-term mode).
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Last updated: 18 July 2026