Mortgage Repayment Calculator Australia 2026: Monthly Payment Guide
Australian Mortgage Repayment Calculator Guide
Mortgage planning starts with the repayment number you can actually budget for. If you are comparing a first home, refinancing offer or investment loan, use the Mortgage Calculator to estimate monthly, fortnightly and weekly home loan repayments from the loan amount, interest rate, term and repayment type.
This guide focuses on the numbers behind the repayment estimate, so you can compare principal-and-interest and interest-only home loan scenarios before speaking with a lender or broker.
What a mortgage repayment estimate needs
1. Loan amount
Start with the amount you expect to borrow, not the purchase price. The loan amount is usually the property price minus your deposit, plus any costs you decide to finance instead of paying upfront.
2. Interest rate
Use the comparison rate or the advertised interest rate you want to model. Small rate changes can materially change monthly repayments, so it is worth testing a higher buffer rate as well as the offer rate.
3. Loan term
Most Australian home loan examples use a 25-year or 30-year term. A longer term can reduce the required repayment, but it usually increases total interest paid over the life of the loan.
4. Repayment frequency
Monthly repayments are useful for budgeting, but many borrowers also compare fortnightly or weekly repayments to line the loan up with their pay cycle. The same loan can feel different when you view the repayment as a weekly, fortnightly or monthly amount.
Example: monthly, fortnightly and weekly repayments
For a $600,000 loan over 30 years at 6.00% interest, a principal-and-interest estimate is roughly:
| Repayment frequency | Estimated repayment |
|---|---|
| Monthly | $3,597 |
| Fortnightly | $1,658 |
| Weekly | $829 |
These are planning estimates, not a lender quote. Fees, package discounts, offset balance, redraw rules and rate changes can all affect the final amount.
Principal-and-interest vs interest-only
Principal-and-interest repayments
Principal-and-interest repayments gradually pay down the loan balance and interest charge together. They are usually the best starting point when you want to understand the long-term cost of a home loan.
Interest-only repayments
Interest-only repayments cover the interest for a set period without reducing the principal. The short-term repayment can look lower, but the loan balance does not fall during that period and later principal-and-interest repayments may be higher.
Use the calculator to compare both repayment types with the same loan amount, interest rate and term. That keeps the trade-off visible instead of comparing different assumptions.
Costs beyond the repayment
Lenders Mortgage Insurance (LMI)
Lenders Mortgage Insurance (LMI) may apply when your deposit is below the lender's preferred loan-to-value ratio, commonly when the deposit is under 20%. LMI is separate from the monthly repayment estimate, but it can affect the cash needed to buy or refinance.
Stamp duty
Stamp duty is another major upfront cost for many property purchases. Use the Stamp Duty Calculator to check a state-based estimate before relying on a deposit target.
Ongoing buffers
A repayment you can afford today may still feel tight after council rates, strata, insurance, repairs and rate rises. Keep a buffer in the budget rather than using the calculator result as the only affordability test.
When to use a payoff calculator instead
The mortgage repayment calculator is best for base repayment scenarios. If you want to model extra repayments, lump sum payments or offset account savings, use the Mortgage Payoff Calculator after you know the standard repayment.
That sequence keeps the planning clean:
- Estimate the regular repayment with the mortgage calculator.
- Add purchase costs such as LMI and stamp duty.
- Test extra repayment or offset strategies with the payoff calculator.
- Compare the result against your pay cycle and emergency buffer.
Quick mortgage planning checklist
- Compare monthly, fortnightly and weekly repayments for the same loan.
- Test principal-and-interest and interest-only scenarios separately.
- Include LMI, stamp duty and settlement costs before setting a deposit target.
- Stress test the repayment with a higher interest rate.
- Use a payoff calculator only after the standard repayment is clear.
Ready to run the numbers? Start with the Mortgage Calculator for Australian home loan repayment estimates, then use the Stamp Duty Calculator and Mortgage Payoff Calculator for the next planning steps.