See what paying a little more each month or fortnight actually does: how many years it cuts off the loan, and how much interest never gets charged. Small numbers, big lever.
Extra repayments
Enter your loan details, then put a number in the extra repayment field — even $50 or $100 a period. The calculator shows the new payoff time, the years saved, and the interest that never gets charged.
The maths is standard amortisation. Fortnightly figures assume 26 payments a year, each half the monthly repayment. The government’s MoneySmart calculator compounds fortnightly instead of halving the monthly repayment, so its fortnightly figure will differ slightly from this one; monthly figures match. The estimate does not include fees, offset accounts or future rate changes.
Estimates only — not a quote, a comparison rate, or an indication that you qualify. Your actual repayments depend on the lender's calculation, fees and your circumstances. General information only; check figures with the MoneySmart mortgage calculator. Fortnightly repayments are calculated as half the monthly repayment, paid 26 times a year.
Reading the result
Your normal repayment is mostly interest in the early years. An extra repayment skips that queue — it goes straight to the loan balance, so every repayment after it is charged slightly less interest. That effect compounds for the whole remaining life of the loan, which is why a modest extra amount can remove years, not months.
The calculator runs your loan twice — once at the standard repayment, once with the extra amount — and shows the difference: the new payoff date, the time saved, and the interest that is never charged. That saved interest is money that stays in your pocket instead of the lender's.
Extra repayments are one lever. The rate you are paying is the other. If your loan has been sitting untouched for a few years, you may be paying what John calls the loyalty tax — the gap between your rate and what the same lender offers new customers. The loyalty tax guide explains how to check yours in about ten minutes.
It assumes the extra amount is paid every period from day one, at a constant rate. It does not model offset accounts, lump sums, redraw, fees, fixed-loan extra-repayment caps, or rate changes — and some fixed loans limit how much extra you can pay. Check your loan's rules before relying on a plan.
Just want the plain repayment figure? Use the repayment calculator. Curious what a lender might let you borrow? Try the borrowing power estimator.
Next step
The calculator shows what extra repayments do at your current rate. John can also check whether the rate itself is the bigger leak — comparing your loan against what lenders are actually writing now, then telling you plainly whether anything is worth doing.
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General information only. Credit assistance is subject to lender policy and responsible lending requirements.
Cross-check
The Australian Government's calculator also models extra repayments. Run the same numbers there — the results should line up.
Open the MoneySmart calculatorWhy long-standing customers often pay more than new ones, and how to check your own rate in about ten minutes.
Read the loyalty tax guideRepayments, QLD stamp duty and borrowing power — all free, all estimates, all cross-checkable.
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