Dolla

Mortgage Repayments & Extra Payments

Work out your home loan repayments. Compare repayment types and see how paying extra could reduce interest and help you finish sooner.

How this tool works

Reviewed 6 September 2026. Monthly repayment estimate, reviewed 12 September 2026.

Calculation outline

  1. Models standard principal and interest or interest-only home loans over 1 to 40 years across monthly, fortnightly, or weekly frequencies.
  2. Simulates the impact of regular extra repayments and one-off lump sums on total interest and loan payoff duration.

Worked example

Example: extra repayments of $200 per month on a $600,000 30-year loan at 6.0% p.a. saves over $50,000 in interest and shortens the loan by over 3 years.

Limits

  • Assumes interest rates remain constant across the loan term; real-world rates and lender package fees will fluctuate.
  • Interest uses one twelfth of the annual rate each month. Weekly and fortnightly amounts are converted to monthly equivalents; lender daily balances and payment timing differ. Any unpaid interest-only balloon is shown separately from payments made.

Sources

This tool provides general information and illustrative estimates only. It does not consider your objectives, financial situation or needs and is not personal financial, tax or legal advice.