Offset Account Calculator
An offset account is a transaction or savings account linked to your home loan. The money in it is taken off your loan balance when interest is worked out, so you pay less interest while your money stays available.
Enter your loan details and your offset balance to see how much interest you could save and how much sooner the loan could be paid off if you keep making the same repayments.
Rates checked on
Rates checked on
Savings you leave in the account. Use 0 if the balance stays the same.
Some loans with an offset charge a yearly fee. Use 0 if there is none.
- Interest saved
- $234,329
- Time saved
- 5 years and 1 month
- Loan paid off in
- 24 years and 11 months
- Interest saved in the first month
- $270.83
- Interest without the offset
- $765,267
- Interest with the offset
- $530,938
Your repayment stays at $3,792 a month. A 100% offset is assumed.
This is an estimate based on the numbers you entered and the assumptions listed below. It isn't an offer of credit or an assessment of what a lender will approve. Figures checked on 29 October 2026.
Read the guide: Mortgage offset accounts: how much interest they save
How it works
The calculator first works out your normal principal-and-interest repayment.
It then runs the loan period by period twice: once with interest on the full balance, and once with interest on the balance minus the offset. The repayment stays the same in both, so the interest saved goes towards paying off the balance.
If you add money to the offset each month, the offset balance grows by that amount over time.
Assumptions
- A full (100%) offset. Some partial offset accounts only offset part of the balance.
- The offset balance is never spent. In real life the balance goes up and down.
- The interest rate stays the same and no account fees are included. Loans with an offset often cost more in fees or have a higher rate, which can reduce the saving.
- Interest on savings in an offset is not earned, so there is no tax on it. This calculator does not compare against a taxed savings account.
Questions people ask
Is an offset account the same as a redraw facility?
No. Money in an offset is your own savings held in a separate account. Money you put into the loan and later redraw is part of the loan, and lenders can limit or change redraw access.
Do I earn interest on my offset balance?
No. Instead you pay less interest on your loan. Because you are not earning interest, there is no tax on the saving.
Does it matter if my salary goes into the offset?
Every day money sits in the offset it reduces the interest charged, so paying income in and spending from a credit card that you pay off in full can increase the saving. Card fees and interest can wipe that out.
Sources
Checked 29 October 2026. Official pages can change; check them before you rely on a figure.