WORKING WEALTH / AUSTRALIA

Mortgage & offset explorer

Compare a principal-and-interest loan with a constant offset and extra repayments.

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Educational scenarios only. All amounts are AUD. These calculations do not assess your circumstances or recommend a product or strategy. Results are estimates, not forecasts or personal financial, credit or tax advice. Inputs stay in your browser and are not saved automatically. The optional Save control stores a scenario on this device; exported files contain your entered amounts. Check official rules and actual provider terms. Prepared by the Working Wealth editorial team, 1 November 2026; independent professional review is pending.

Assumptions and limits

Monthly principal-and-interest repayments at a constant annual rate ÷ 12. The base repayment is calculated without offset. Scenario payments keep that repayment and add the extra amount. Interest applies to max(0, loan balance − constant offset). The offset remains separate cash; it does not repay principal. No fees, rate changes, daily lender rounding, redraw, partial offset or interest-only periods. Interest avoided excludes any extra product costs.

References and verification

Official references checked for this release on 1 November 2026. Rules and product terms can change.