Generate a complete Australian mortgage amortisation schedule showing every repayment, principal, interest, remaining balance and the impact of extra repayments.
📖 10 min read · ⏱️ Calculator time: ~30 seconds
| Item | Standard | With extra |
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Results are estimates only. Actual repayment schedules may vary depending on your lender's interest calculation method, fees, rate changes and loan conditions.
| Year | Opening balance | Principal paid | Interest paid | Closing balance |
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| Year | Opening balance | Principal paid | Interest paid | Closing balance |
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| # | Date | Opening balance | Payment | Principal | Interest | Closing balance |
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An amortisation schedule is a table showing every repayment over the life of a loan, broken down into the principal and interest components, along with the remaining balance after each payment. It's the clearest way to see exactly where your money goes each month — and how that changes as the loan matures.
Amortisation is the process of paying off a loan through regular scheduled payments over time. Each payment you make to your lender covers two components: interest (the lender's fee for the loan) and principal (repayment of the original borrowed amount). The key insight of amortisation is how the split between interest and principal changes over the life of the loan.
In the early years of an Australian home loan, the majority of each repayment goes toward interest — not reducing the loan balance. Over time, as the balance reduces, the proportion going to principal increases. This is why the early years of a mortgage feel "expensive" and why making extra repayments early has such a powerful effect on the total loan cost.
The principal is the amount you actually borrowed and still owe — reducing it is the only thing that brings you closer to owning your home outright. The interest is the cost of borrowing, calculated daily on your outstanding balance and typically charged to your loan monthly. Every dollar that goes to principal permanently lowers the balance interest is calculated on; every dollar that goes to interest is gone, with no effect on your balance.
Interest is calculated on the current outstanding balance, which is at its highest right at the start of the loan. Since your scheduled repayment amount stays roughly constant, a bigger slice of it is consumed by interest early on, leaving less for principal. As the balance shrinks year by year, the interest portion shrinks with it and the principal portion grows — until, in the final years, almost the entire repayment reduces the balance.
Each row of the schedule generated above shows: the opening balance for that period, the payment made, how much of it was principal vs interest, and the resulting closing balance. Use the Full Payment Schedule table to step through individual payments, filter by year, or jump straight to a specific payment number (for example, "payment #120" to see where you'll be in exactly 10 years on a monthly schedule).
Repayment frequency changes more than convenience. Because there are 26 fortnights (or 52 weeks) in a year but only 12 months, paying fortnightly or weekly results in the equivalent of one extra monthly repayment every year — entirely directed at principal. Use the Weekly vs Fortnightly vs Monthly panel in the calculator above to compare your own numbers.
Extra repayments go straight to principal, reducing the balance interest is calculated on from that point forward. Because interest compounds daily on a lower and lower balance, consistent extra repayments — even modest ones — produce savings that grow disproportionately larger the longer the loan runs. Enter an amount in the "Extra monthly payment" field above to see the effect on your own schedule.
A lump sum — a bonus, inheritance, or tax refund — applied directly to your loan produces an immediate, permanent drop in the balance, and therefore in every future interest calculation. The earlier in the loan a lump sum is applied, the larger its lifetime impact, since it has more time remaining to keep "not accruing" interest.
An offset account is a linked transaction account whose balance is subtracted from your loan balance before interest is calculated each day — without the funds ever leaving your control. A $600,000 loan with a $40,000 offset balance is charged interest on $560,000 only. The Offset Account Comparison panel above isolates exactly how much interest and time an offset balance saves on top of any extra repayments and lump sums you've entered.
This calculator's amortisation math applies most cleanly to variable rate loans, where extra repayments, lump sums and offset accounts are usually unrestricted. Fixed rate loans typically cap extra repayments at a set amount per year and rarely offer a 100% offset account — check your loan's specific terms before making large extra repayments on a fixed rate, as exceeding the cap can trigger break costs.
Use the CSV button above to export the complete payment-by-payment schedule into a spreadsheet, the PDF button for a shareable summary report, or Print for a paper copy. All three reflect whatever extra repayments, lump sum and offset balance you've entered.
Take a $600,000 loan at 6.25% over 30 years. The standard schedule takes the full 30 years and accrues substantial total interest. Add $500/month in extra repayments and a $10,000 lump sum today, and the enhanced yearly summary above recalculates the entire schedule — typically cutting several years off the term and tens of thousands off total interest. Layer in an offset balance and the payoff date moves forward again, since interest is now calculated on a lower effective balance every single day. Try your own numbers in the calculator above to see the exact figures for your loan.
| Term | Meaning |
|---|---|
| Principal | The amount you actually owe, excluding interest. |
| Amortisation | The gradual reduction of a loan balance through scheduled repayments. |
| Offset account | A linked account whose balance reduces the interest charged on your loan. |
| Redraw | Access to extra repayments already made, held within the loan itself. |
| Remaining balance | The amount still owed at any point in the schedule. |
| Comparison rate | Interest rate plus most fees, for fairer comparison between loans. |
| P&I | Principal and Interest — a repayment type that reduces the balance with every payment. |
The standard mortgage repayment formula is:
Where: M = monthly payment | P = loan principal | r = monthly interest rate (annual rate ÷ 12) | n = total number of payments (years × 12)
| Year | Annual Principal Paid | Annual Interest Paid | Remaining Balance | Cumulative Interest |
|---|---|---|---|---|
| Year 1 | $5,684 | $38,716 | $594,316 | $38,716 |
| Year 5 | $7,807 | $36,593 | $561,826 | $191,434 |
| Year 10 | $10,791 | $33,609 | $510,099 | $374,539 |
| Year 15 | $14,913 | $29,487 | $439,337 | $543,239 |
| Year 20 | $20,617 | $23,783 | $340,777 | $691,236 |
| Year 25 | $28,509 | $15,891 | $194,791 | $810,684 |
| Year 30 | $39,431 | $4,969 | $0 | $852,120 |
Making extra repayments early in the loan term has a disproportionately large impact because the balance is highest in the early years, so every dollar of principal reduction saves the most in future interest. Here is the impact of a one-off $10,000 extra payment made at different times on a $600,000 loan at 6.5% over 30 years:
| When Extra Payment Made | Interest Saved | Time Saved |
|---|---|---|
| Year 1 (early in loan) | ~$33,000 | ~10 months |
| Year 10 (mid-loan) | ~$19,000 | ~6 months |
| Year 20 (late in loan) | ~$8,000 | ~2 months |
In Australia, most home loans calculate interest daily and charge it monthly. Your daily interest is: Loan balance × (Annual rate ÷ 365). This means any extra repayment you make reduces the outstanding balance immediately, reducing the next day's interest calculation from that moment forward. An offset account works on the same principle — funds in offset reduce the balance for interest calculation purposes while remaining accessible.
This schedule shows where you stand today — these tools help you plan what to do next:
An amortisation schedule turns an abstract loan balance into a concrete, payment-by-payment picture of exactly how your money is being used. Use the calculator above to generate your own schedule, test extra repayments, a lump sum, an offset balance, and a different repayment frequency, then export the result as a CSV or PDF to keep for your records. Pair it with our Mortgage, Payoff, and Borrowing Power calculators for the complete picture of your home loan.
What is an amortisation schedule?
An amortisation schedule is a table showing every payment over the life of a loan, broken down into principal and interest components. It shows how the loan balance reduces over time and how much total interest is paid. The calculator above generates a full amortisation schedule you can step through year by year.
How much of my first mortgage payment goes to interest?
On a $600,000 loan at 6.5% p.a., your first monthly payment of approximately $3,792 consists of roughly $3,250 in interest and only $542 in principal — meaning about 86% goes to the lender as interest, not reducing your loan balance. This ratio gradually shifts over 30 years until the final payment is almost entirely principal.
How can I pay off my mortgage faster in Australia?
The most effective strategies are: make fortnightly instead of monthly repayments (equivalent to one extra monthly payment per year), make lump sum extra repayments whenever possible, use an offset account to reduce daily interest while keeping funds accessible, and consider rounding up repayments to the nearest hundred.
Does an offset account reduce amortisation?
Yes. Money held in a 100% offset account reduces the loan balance for daily interest calculation. If you have $50,000 in offset on a $600,000 loan, you pay interest on $550,000. This effectively reduces your amortisation period — the same repayment amount pays off the loan faster because less goes to interest each period.
What is the difference between P&I and interest-only repayments?
Principal and Interest (P&I) repayments include both an interest component and a principal reduction — your loan balance decreases with every payment. Interest-only repayments cover only the interest charge — the balance does not reduce at all. Most owner-occupiers use P&I; some investors use interest-only for cash flow management, though the balance must eventually be repaid.
How does extra monthly payment affect amortisation?
Extra repayments directly reduce the principal, shortening the amortisation period. On a $600,000 loan at 6.5% over 30 years: $200/month extra saves approximately $86,000 in interest and cuts about 3.5 years. $500/month extra saves approximately $163,000 and cuts about 7 years. The savings are greatest when extra payments are made consistently throughout the loan.
Can I get an amortisation schedule from my lender?
Yes. Your lender or mortgage broker can provide a full amortisation schedule. Many Australian online banking platforms also show a payment breakdown. This calculator generates an indicative schedule based on the inputs you enter — actual schedules may vary depending on your lender's exact calculation method and any rate changes.
What happens to my amortisation schedule if rates change?
On a variable rate loan, a rate change alters the interest component of each payment. If your repayment amount stays the same (fixed minimum), more or less goes to principal depending on the rate direction. Rate increases slow principal repayment; rate decreases accelerate it. The amortisation schedule resets with each rate change.
What is principal?
Principal is the amount you actually borrowed and still owe, excluding interest. Reducing the principal is the only thing that brings you closer to owning your home outright — every extra repayment or lump sum goes straight to principal.
What is interest?
Interest is the cost charged by your lender for borrowing the money, calculated daily on your outstanding balance and typically debited to your loan monthly. It doesn't reduce your balance — only the principal portion of a payment does that.
Why does the interest portion reduce over time?
Interest is calculated on the current outstanding balance, which shrinks every time you make a principal repayment. As the balance falls, the interest charged each period falls with it, so a larger share of each fixed repayment is left over to reduce principal — a self-reinforcing effect that accelerates toward the end of the loan.
Can I download my amortisation schedule?
Yes — use the CSV button above to export the full payment-by-payment schedule to a spreadsheet, or the PDF button for a summary report. Both reflect any extra repayments, lump sum and offset balance you've entered.
Weekly vs fortnightly amortisation — which is better?
Both produce a similar result, since each is roughly equivalent to one extra monthly repayment per year compared with paying strictly monthly. Fortnightly is the more commonly offered option; compare your own numbers in the Weekly vs Fortnightly vs Monthly panel above.
Does this calculator support monthly amortisation?
Yes — monthly is the default and most common repayment frequency for Australian home loans. You can switch to fortnightly or weekly using the Repayment frequency selector above.
Can I use this calculator for an investment property loan?
Yes, the amortisation maths is the same for investment and owner-occupier loans. The main practical difference is on the tax side — interest on an investment loan is generally tax-deductible, which doesn't apply to an owner-occupied home.
Can I use this calculator for a fixed-rate loan?
Yes, for the standard schedule. Just be aware that fixed rate loans usually cap extra repayments at a set amount per year and can charge break costs if you exceed it — check your loan's specific terms before relying on a schedule that includes large extra repayments or a lump sum.
Can I use this calculator for a variable-rate loan?
Yes — this is the calculator's primary use case. Variable rate loans generally allow unrestricted extra repayments, lump sums and offset accounts, all of which this calculator models.
How accurate is this amortisation calculator?
It uses standard Australian amortisation formulas and is a solid planning estimate. Actual figures can vary slightly based on your lender's exact daily interest calculation method, fees, and any rate changes over the life of the loan — always confirm with your lender for an official schedule.
Can I export my amortisation schedule?
Yes, click the CSV button above to download the complete payment-by-payment schedule as a spreadsheet file, ready to open in Excel or Google Sheets.
Can I print the amortisation schedule?
Yes, use the Print button above, or your browser's print function, to produce a paper or PDF copy of the current page including your results.
What happens after I make a lump sum repayment?
A lump sum immediately reduces your outstanding balance, which lowers every future interest calculation for the remainder of the loan. Your scheduled minimum repayment typically stays the same, so the loan simply finishes sooner and with less total interest — see the effect in the Enhanced Yearly Summary above.
Why are extra repayments made early in the loan more effective?
Because the balance — and therefore the daily interest charge — is highest early in the loan. Reducing the balance sooner means more years of avoided interest compared with making the same extra repayment later, when the balance (and daily interest) is already lower.
What is "remaining balance" on an amortisation schedule?
Remaining balance is the amount you still owe at any point in the schedule — it starts at your original loan amount and reduces with every principal repayment until it reaches zero at payoff.
Can I compare two amortisation schedules side by side?
Yes — the Balance Over Time chart above plots your standard repayment schedule against your enhanced scenario (with extra repayments, lump sum and offset applied) on the same graph, so you can see exactly how much sooner the enhanced schedule reaches zero.
Does the calculator show a yearly summary as well as individual payments?
Yes — the Annual Amortisation Summary shows your standard schedule year by year, the Enhanced Yearly Summary shows the same view with extra repayments, lump sum and offset applied, and the Full Payment Schedule lets you drill down to individual payments with filter-by-year and jump-to-payment controls.
How do I find a specific payment in my schedule?
Use the "Jump to payment #" field in the Full Payment Schedule section above — enter a payment number (for example, 120 for 10 years into a monthly schedule) to see that payment and the ones immediately around it.
Does my minimum repayment change as my balance goes down?
On most standard Australian home loans, no — your scheduled minimum repayment stays the same throughout the loan unless you refinance, the rate changes, or you specifically ask your lender to recalculate it. The benefit of a lower balance shows up as a shorter remaining term, not a lower repayment.
Is the amortisation schedule the same as my loan contract?
No — this calculator produces an indicative schedule based on the figures you enter. Your actual loan contract and any official schedule from your lender may differ slightly due to exact interest calculation methods, fees, or rate changes over time.