Extra Repayments Calculator
See how much interest — and how many years — extra repayments cut from your home loan. Add a regular extra amount, a one-off lump sum, or switch to fortnightly repayments.
Interest saved
$106,401
Time cut from your loan
3 yrs 11 mths
Loan paid off in
26 yrs 1 mth
Minimum repayments only
- Repayment
- $3,593.45 / month
- Total interest
- $693,641
- Paid off in
- 30 yrs
With extra repayments
- Repayment
- $3,793.45 / month
- Total interest
- $587,240
- Paid off in
- 26 yrs 1 mth
Balance over time
How extra repayments work
Home loan interest is charged on your outstanding balance, recalculated every repayment period. Anything you pay above the minimum goes straight to principal, so every future interest charge is computed on a smaller balance. The earlier the extra dollars land, the longer they have to compound in your favour — which is why a lump sum today often saves more than the same amount spread over many years.
Pair extra repayments with a sharp rate for the biggest effect — see our home loan comparison and the offset account guide (an offset gives a similar interest saving while keeping the cash accessible).
FAQs
How do extra repayments save interest?
Interest is calculated on your outstanding balance. Every extra dollar reduces that balance immediately, so all future interest is charged on a smaller amount — and the effect compounds over the remaining term.
Is it better to pay fortnightly instead of monthly?
Half your monthly repayment every fortnight means 26 half-payments — effectively 13 monthly repayments a year instead of 12. The extra annual repayment shortens the loan. Model it with the frequency selector above.
Are there limits on extra repayments?
Most variable loans allow unlimited extra repayments. Fixed-rate loans often cap them (commonly $10,000–$30,000 a year) and may charge break costs beyond that. Check your loan terms first.
Is this calculator financial advice?
No — it gives general estimates using a simplified model (constant rate, regular repayments, no fees). Your lender’s figures will differ. Confirm details with your lender before deciding.
Estimates only, for general information. Assumes a constant interest rate and regular repayments, and excludes fees and charges. Not financial advice — confirm figures with your lender.