Repayments, LVR, LMI, offset savings and the 3% buffer, in Australian dollars.
Who this is for: Buying a home in Australia.
$
$
20.0% of the price
%
years
RepaymentsMonthly
Repayment frequency
$
Savings in an offset account reduce the balance interest is charged on.
Deposit and LMINo LMI
$
Added to the loan when the LVR is over 80%. Insurers price it, so enter your quote.
Monthly, fortnightly or weekly
The same loan repaid on each schedule, each amount worked out for the full term.
Frequency
Repayment
Per year
Total interest
Monthly
$3,796.07
$45,553
$726,587
Fortnightly
$1,751.19
$45,531
$725,930
Weekly
$875.42
$45,522
$725,649
How the repayment is worked out
1Loan$800,000 − $160,000 = $640,000
2Rate per month5.90% ÷ 12 = 0.49167%
3Repayment = L × i ÷ (1 − (1 + i)^−n)$640,000 × 0.0049167 ÷ (1 − 1.0049167^−360) = $3,796.07
4Serviceability check5.90% + 3 = 8.90% → $5,103.60 a monthAPRA expects lenders to test your repayments at least 3 percentage points above the loan rate.
Year-by-year schedule
How each year's payments split between interest and the balance you owe.
Year
Paid
Principal
Interest
Balance
1
$45,553
$8,007
$37,546
$631,993
2
$45,553
$8,493
$37,060
$623,500
3
$45,553
$9,007
$36,546
$614,493
Calculated in your browser — the numbers you enter are never sent to our servers.
Work out Australian home loan repayments monthly, fortnightly or weekly, with the loan-to-value ratio, Lenders Mortgage Insurance above 80%, the 5% Deposit Scheme, interest-only periods, the savings from an offset account and the repayment your lender will assess you at under APRA’s 3% buffer.
Best for: First home buyers, Fortnightly vs monthly, Offset accounts, Interest-only periods
Updated September 2026 · Estimates only, not financial advice.
Paying half the monthly amount each fortnight saves $152,692 on this loan
There are two ways to repay fortnightly, and only one of them saves money. If the fortnightly repayment is worked out for the full term — $1,751.19 on the example’s $640,000 at 5.9% over 30 years — you pay the loan off on schedule, with total interest of $725,930, almost the same as monthly.
If instead you pay half the monthly repayment every fortnight, $1,898.04, you make 26 half-payments a year: the same as 13 monthly repayments instead of 12. That extra month’s worth each year goes straight to principal. On the example loan it cuts the term by about 5.4 years and saves $152,692 in interest. The calculator shows this saving whenever you choose fortnightly principal-and-interest repayments.
A 20% deposit avoids LMI; below that, the insurance is usually added to the loan
The loan-to-value ratio is the loan as a share of the property’s value. Most lenders charge Lenders Mortgage Insurance when you borrow more than 80%. LMI protects the lender if you default, not you, and the premium — set by the insurer, rising steeply as the LVR climbs — is usually added to the loan, so you pay interest on it.
The example’s $160,000 deposit on $800,000 is exactly 20%, so the $640,000 loan sits at 80% LVR with no LMI. With a 10% deposit and a $15,000 LMI quote, the loan becomes $735,000 at 90% LVR and the monthly repayment rises to $4,359.55. Because LMI prices differ by insurer and lender, enter the quote you are given rather than relying on an estimate.
With the 5% Deposit Scheme, a first home buyer can borrow 95% without LMI
Under the Australian Government 5% Deposit Scheme, administered by Housing Australia through participating lenders, eligible first home buyers can buy with a deposit of as little as 5% and pay no LMI; the government guarantees the gap between the deposit and 20%. Since 1 October 2025 there are no income caps and no limit on places, and the property price caps are higher — $1.5 million in Sydney, for example — with lower caps in other cities and regions.
On the example home, a $40,000 deposit under the scheme means a $760,000 loan at 95% LVR, a monthly repayment of $4,507.84 and $862,821 of interest over 30 years. No LMI is added, but the bigger loan still costs $136,234 more in interest than the 20%-deposit version. Tick the scheme box to model it; check the price cap for your area with your lender.
Keeping $50,000 in offset saves $198,470 and more than four years
An offset account is a transaction account linked to your home loan. Its balance is subtracted from the loan balance before interest is calculated, so every dollar in it earns, in effect, your mortgage rate, tax-free. If you keep making the same repayment, more of each one goes to principal.
With $50,000 kept in offset on the example loan, and the repayment unchanged at $3,796.07, the loan is paid off about 4.3 years sooner and interest falls by $198,470. The calculator assumes the offset balance stays constant; in real life it rises and falls with your savings, so treat the figure as what that average balance would be worth.
Five interest-only years: $3,147 a month, then $4,085 once principal starts
During an interest-only period the repayment covers interest alone — $3,146.67 a month on the example loan — and the balance does not fall. When the period ends, the whole $640,000 must be repaid over the remaining 25 years, so the principal-and-interest repayment jumps to $4,084.50, and total interest rises to $774,149 against $726,587 without the interest-only period.
Owner-occupiers usually get interest-only periods of up to five years, and investors use them more often. Plan for the step up: the repayment after the period is shown in the result panel whenever interest-only is selected.
Your lender will test a $5,104 repayment on this loan, not $3,796
APRA expects banks to assess whether you could keep up repayments if rates rose by at least 3 percentage points above the loan rate. At 5.9% the assessment rate is 8.9%, and the monthly repayment on $640,000 over 30 years at that rate is $5,103.60. Your income, expenses and other debts have to cover that figure, which is why borrowing power usually looks smaller than repayment calculators suggest. APRA confirmed the 3% buffer again in 2026.
Stamp duty, first home buyer grants and duty concessions are set by each state and territory and are not calculated here; add them to the cash you need upfront. Lenders also calculate interest daily and charge it monthly, so their repayment figures can differ from these by a few dollars. Treat this as an estimate and rely on your lender’s loan offer.
Worked example
An $800,000 home with a 20% deposit at 5.9% over 30 years, repaid monthly.
Worked example
Loan (80% LVR, no LMI) = $640,000
Monthly repayment = $3,796.07
Total interest = $726,587
Assessed at 8.9% = $5,103.60 a month
Limitations
Stamp duty and first home buyer concessions vary by state and are not calculated.
LMI is priced by insurers, so the calculator uses the quote you enter rather than estimating it.
Lenders calculate interest daily and charge it monthly; this uses the standard per-period approximation.
Frequently Asked Questions
Are fortnightly repayments cheaper?
Only if you pay half the monthly amount every fortnight. That makes 26 half-payments, or 13 monthly repayments a year, and on a $640,000 loan at 5.9% over 30 years it saves about $152,692 and 5.4 years.
When do I pay Lenders Mortgage Insurance?
Usually when you borrow more than 80% of the property’s value. First home buyers using the 5% Deposit Scheme can borrow up to 95% without LMI.
What is the serviceability buffer?
APRA expects lenders to check you could still make the repayments at a rate at least 3 percentage points above your loan rate. At 5.9% that is 8.9%.
Sources & References
Figures on this page are checked against primary, authoritative sources. Links open in a new tab.
Results are estimates based on the figures you enter and standard formulas. Rates, fees, taxes, and lender terms vary and change over time, so confirm important numbers with your lender or a qualified professional. This is educational information, not financial advice.
Published an Australian mortgage calculator split out of the US one: monthly, fortnightly and weekly repayments, principal and interest or interest-only.
LVR and Lenders Mortgage Insurance, the 5% Deposit Scheme, offset-account savings, half-monthly fortnightly repayments and APRA’s 3% serviceability buffer.
Added an automated formula suite with hand-computed repayments and offset and interest-only identities.
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