Australian Mortgage Calculator

Calculate your home loan repayments for principal & interest or interest-only loans. Includes LMI estimate, council rates, and strata fees. All figures in AUD.

$
$20%
% p.a.
Monthly Repayment
A$4,195
A$3,920 principal & interest
Principal & Interest: $3,920
Council Rates: $150
Insurance: $125
Loan Amount
A$640,000
Total Interest
A$771,129
LVR
80.0%
Total Repaid
A$1,411,129

Compare principal & interest against interest-only for your A$640,000 loan over 30 years.

Principal & Interest
A$3,920/mo
Total interest: A$771,129
Builds equity from day one
Interest Only (30 years)
A$3,307/mo
Total interest (full IO): A$1,190,400
+A$419,271 more interest than P&I
Monthly Saving (IO vs P&I)
A$613
IO has lower payment
Extra Interest Cost (IO)
A$419,271
Over full term
No Equity Built (IO)
A$640,000
Balance unchanged during IO period
$
$
$
Total Upfront Cash Required
A$192,600
Deposit + stamp duty + all fees
Deposit: $160,000
Stamp Duty: $30,000
Legal Fees: $2,000
Inspections: $600
Deposit
A$160,000
Stamp Duty
A$30,000
LMI Premium
None
Other Costs
A$2,600
Total Upfront
A$192,600
LVR
80.0%
No LMI needed

How to Use This Australian Mortgage Calculator

Enter your Property Value and Deposit to see your estimated monthly repayment. Choose between Principal & Interest (P&I) or Interest Only (IO). The calculator estimates Lender's Mortgage Insurance (LMI) if your deposit is under 20% (LVR above 80%) and includes it in the loan amount.

Use "More options" to add council rates, strata fees (for apartments/units), and home insurance for a complete monthly cost picture.

The Formula

P&I Monthly Repayment = L × [r(1+r)^n] / [(1+r)^n - 1]

Where:
L = Loan amount (including LMI if applicable)
r = Monthly interest rate (annual rate ÷ 12)
n = Total months (years × 12)

Interest Only = Loan Amount × Annual Rate / 12

LMI Estimate (LVR 80–85%): ~1% of loan
LMI Estimate (LVR 85–90%): ~2% of loan
LMI Estimate (LVR 90–95%): ~3.5% of loan

Example: Buying in Sydney, NSW

Tom and Emma's First Home

Purchasing a 2-bedroom apartment in Parramatta, Western Sydney.

Property Value$850,000
Deposit (20%)$170,000
Loan Amount$680,000
Rate (6.20%, 30 years P&I)$4,163/mo
Council Rates$150/mo
Strata Fees$600/mo
Insurance (landlord/home)$125/mo
Total Monthly Cost$5,038
Total Interest (30 yrs)$817,600

If they had only a 15% deposit ($127,500), LMI would add ~$14,960 to the loan, increasing the monthly repayment by ~$92.

Frequently Asked Questions

The Reserve Bank of Australia (RBA) sets the cash rate, which directly influences variable mortgage rates. When the RBA raises rates, lenders typically pass the increase on within days. Fixed-rate mortgages are unaffected during the fixed period. Australia's standard variable rate is typically 1.5–2.5% above the cash rate.
Technically as little as 5% with LMI. To avoid LMI, you need 20%. First home buyers can access the First Home Guarantee (5% deposit with no LMI, government backing), and the Family Home Guarantee (2% for single parents). Some lenders accept genuine savings of at least 5% of the purchase price.
P&I is almost always better for owner-occupiers — you build equity and save significantly on total interest. Interest-only (IO) is popular with investors for cash flow and tax deduction purposes during the IO period. IO rates are typically 0.2–0.5% higher than P&I rates, and most lenders limit IO periods to 5 years (up to 10 for investment loans).
An offset account is a transaction account linked to your mortgage. The balance in the offset reduces the loan balance for interest calculation. $50,000 in offset on a $500,000 loan means you only pay interest on $450,000. A redraw facility lets you access extra repayments you've made — less tax-effective for investors but useful for owner-occupiers.

Related Australian Calculators

📋Stamp Duty Calculator 🛡️LMI Calculator 🏠First Home Grant 💰Offset Account 📊Interest Only 🏡Rental Yield

Sources & References