Mortgage Repayment Calculator Australia
Free Australian mortgage repayment calculator. Enter your loan amount, interest rate, and loan term to instantly see repayment amounts for monthly, fortnightly, or weekly frequencies. Compare principal & interest vs interest-only repayments and view total interest payable over the life of the loan.
Loan Details
P&I / IOMonthly Repayment
$0.00
Total Interest
$0
Total Loan Cost
$0
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Understanding mortgage repayments in Australia
Your mortgage repayment amount depends on three main factors: the loan amount (principal), the interest rate, and the loan term. Most Australian home loans are structured as principal and interest (P&I), meaning each repayment reduces both the interest owed and the outstanding loan balance.
Repayment frequency matters
Switching from monthly to fortnightly repayments is one of the simplest ways to pay off your mortgage faster. Because there are 26 fortnights in a year, you effectively make 13 monthly payments instead of 12. This extra payment goes straight to reducing your principal, which can save tens of thousands of dollars in interest over the life of a 30-year loan.
Interest-only vs principal & interest
Interest-only loans have lower initial repayments because you're not paying down the principal. They're commonly used by property investors for tax purposes. However, you'll pay significantly more interest over the life of the loan, and your repayments will jump when the interest-only period ends (typically after 1-5 years).
Frequently asked questions
Mortgage repayments are calculated using an amortisation formula that factors in your loan amount, interest rate, and loan term. For P&I loans, each repayment covers both interest and a portion of the principal. Early repayments are mostly interest, shifting toward principal over time.
Paying fortnightly can save you money because you effectively make 26 half-payments per year (equivalent to 13 monthly payments instead of 12). This extra payment goes directly to reducing your principal, potentially saving thousands in interest and shortening your loan term.
Principal & Interest (P&I) repayments pay down the loan balance plus interest each period. Interest-only repayments only cover the interest charged — your loan balance stays the same. Interest-only periods are typically 1-5 years, after which the loan converts to P&I.
Interest rates vary by lender and product. As of 2024-25, competitive variable rates for owner-occupiers are around 5.9-6.5% p.a. Fixed rates depend on the term. Compare rates from multiple lenders and consider the comparison rate, which includes fees.
Even small extra repayments can significantly reduce your loan term and total interest. For example, paying an extra $100/month on a $500,000 loan at 6% could save over $50,000 in interest and cut years off your mortgage. Check your loan for any restrictions on extra repayments.
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