FREE CALCULATOR · NO SIGN-UP
See how an extra payment changes a fixed-rate mortgage. Compare three scenarios on the same remaining balance, with clear assumptions and a downloadable schedule.
Your numbers stay in your browser. No account or submission to a bank.
Keep the remaining term; recalculate payments on the lower balance.
Fees included: — · Months saved: —
Keep the original payment; finish sooner, with a smaller final payment if needed.
Fees included: — · Months saved: —
As in B, plus an extra amount each month until payoff.
Fees included: — · Months saved: —
Nominal estimates, without discounting: no option is personal advice. The extra principal is paid upfront; it is not an additional borrowing cost.
| Month | Payment | Principal | Interest | Balance |
|---|
No future instalments: the initial overpayment covers the principal.
CSV uses comma separators and decimal points. Month 0 records the initial overpayment and one-time fees in a separate column. Monthly amounts are rounded to two decimals only for export.
EXAMPLE · 150,000 / 3.5% / 20Y
150,000 remaining, 3.5% nominal interest, 20 years, 10,000 upfront and no fees: the original payment is about 869.94. A reduces it to 811.94; B finishes in 218 months and avoids about 9,495.72 in interest. With another 100 monthly, C finishes in 188 months. These are hypothetical examples in the same currency.
A releases more room in a monthly budget; B and C repay principal faster. Consider liquidity, other commitments and contract terms. The calculator does not know your financial circumstances.
It is the difference between future interest in the current schedule and the scenario, minus entered fees. It is not an annual return, does not account for the time value of money and can be negative.
The mathematical model uses annual nominal interest divided by 12 and monthly payments. It does not determine any country’s tax, penalty or compounding rules. Currency selection changes display units without converting amounts.
Monthly fixed-rate model with level principal-and-interest payments at month end. Extras reduce principal. It excludes taxes, insurance, daily interest, future rate changes and alternative returns. The final payment covers only what is still due. A lender may use different rounding or compounding conventions or may not offer both repayment options: obtain a contractual quote before deciding.
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