Find out how much interest and time you save by paying more than the minimum on your home loan, with extra weekly, fortnightly or monthly repayments, a one-off lump sum, or both. Adding just $200 a month to a $600,000 loan at 6.49% over 30 years saves about $121,670 in interest and clears the loan 4 years early.
Extra Repayments Calculator
Pay off your home loan sooner · Updated 13 October 2026
- Loan paid off sooner by
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- New loan term
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- Required repayment
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- Your repayment with the extra
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- Interest on the original schedule
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- Interest with extra repayments
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Principal and interest, rate unchanged for the whole term, interest charged each repayment period. Fixed-rate loans may limit extra repayments or charge break costs; check your loan terms.
Why extra repayments save so much
Interest is charged on the outstanding balance. Every extra dollar you pay goes straight to the principal, so the next interest charge is a little smaller, and the saving repeats every repayment for the rest of the loan. Moneysmart points out that extra payments early in the loan, when most of each repayment is interest, save the most.
- The calculator first works out the required repayment for your balance, rate and remaining term.
- It then adds your extra amount to each repayment and takes any lump sum off the balance today.
- Each period it charges interest on the balance (rate ÷ 12, 26 or 52) and subtracts the repayment, until the loan is paid off.
How much different amounts save
| Extra each month | Interest saved | Paid off sooner by | New loan term |
|---|---|---|---|
| $100 | $66,980 | 2 years 2 months | 27 years 10 months |
| $200 | $121,670 | 4 years | 26 years |
| $500 | $240,096 | 8 years 1 month | 21 years 11 months |
| $1,000 | $358,720 | 12 years 6 months | 17 years 6 months |
| Lump sum paid now | Interest saved | Paid off sooner by |
|---|---|---|
| $10,000 | $56,632 | 1 year 5 months |
| $20,000 | $107,490 | 2 years 9 months |
| $50,000 | $233,655 | 6 years 2 months |
Weekly, fortnightly or monthly?
If you simply switch to the fortnightly repayment your lender calculates, the saving is small: the required fortnightly repayment on the loan above is $1,747.70, and total interest falls only from about $763,847 to $763,204. The real saving comes from the popular trick of paying half the monthly repayment every fortnight. There are 26 fortnights in a year, so you make the equivalent of 13 monthly repayments instead of 12.
On this loan, half the monthly repayment is $1,894.23 a fortnight, which is $146.53 more than required. Paying that way clears the loan in 24 years 2 months and saves about $175,018 in interest compared with the required fortnightly repayments. To try it above, choose Fortnightly and enter an extra $147 (the field takes whole dollars): the loan is paid off in 24 years 1 month, saving about $175,436.
Before you pay extra
- Variable loans usually allow extra repayments, often without a fee. Check with your lender.
- Fixed-rate loans often cap extra repayments during the fixed period, and paying more than the cap can trigger break costs. Check your contract or ask your lender.
- Redraw: extra repayments can usually be taken back out through a redraw facility, but some lenders limit redraws, charge a fee or take time to release the money.
- Offset account: keeping the same money in an offset saves the same interest while leaving it easier to reach. Compare both with the offset account calculator.
- Other debts: paying off a credit card or personal loan at a higher rate usually saves more than extra home loan repayments.
FAQs
Do extra repayments lower my required repayment?
Usually not. Most lenders keep your required repayment the same and let the loan finish early, which is what this calculator assumes. Some lenders will recalculate a lower repayment if you ask; that improves cash flow but saves less interest.
Is it better to pay a lump sum or extra each month?
Money paid earlier saves more interest. A $20,000 lump sum today saves about $107,490 on the loan above, while the same $20,000 paid as $200 a month over the first 100 months saves about $80,250, because most of it reaches the loan later.
How do rate rises affect this?
Higher rates make every extra dollar save more. With the Reserve Bank’s cash rate at 4.60% since 30 September 2026, paying a little extra is also a buffer: if rates rise again, you are already ahead of your schedule.
Related calculators
- Offset Account CalculatorInterest saved by savings in an offset
- Home Loan Repayment CalculatorYour required repayment
- Borrowing Power CalculatorHow much a lender may let you borrow
Sources
- Moneysmart (ASIC): Pay off your mortgage faster
- Moneysmart (ASIC): Mortgage offset accounts · offset versus redraw
- Reserve Bank of Australia: Cash rate target · 4.60% from 30 September 2026
- InDaily (AAP): Canstar average owner-occupier variable rate of 6.49% · 29 September 2026
Figures current as of 13 October 2026
Each formula is checked against a separate test sheet with at least three worked examples. Results are estimates based on the numbers you enter and the published rules; your actual figures may differ. This is general information, not financial or tax advice.
Spotted a mistake? Contact us and we will fix it and update the date above.