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Offset Calculator

Calculate how many years you could take off your home loan, and how much you could save in interest simply by using an offset sub-account to pay off your home loan faster.

An offset sub-account acts just like a regular transaction account, with one key difference. The amount saved in your offset account is subtracted from your existing loan balance, so the amount of interest payable is lower and you’ll save on your monthly interest repayments.

Estimated savings from offset graph

Total interest saved

16 years, 1 months
13 years, 11 months

Calculator assumptions

How to use our offset calculator

Using our mortgage offset sub-account calculator is simple. You’ll need to input figures including:

  • Your loan amount
  • Interest rate
  • The term of your loan
  • Repayment frequency such as whether it’s monthly or fortnightly
  • Your starting account balance
  • Net monthly contribution.
borrower comparing refinancing options borrower comparing refinancing options

What do I need to enter into the offset sub-account calculator?

The results will show your regular monthly repayments, the total mortgage amount, the interest paid, and the interest you can save.

This calculator comes in handy if you’re hoping to determine whether or not an offset sub-account is the right choice for you given your financial situation. If you don’t already have one, you can use it to see the difference when you decide to add this feature to your regular home loan.

If you don't plan on making regular payments into your offset sub-account but have a good idea of what you believe will be the average amount you will keep in it, simply put this amount in the starting balance and leave the net monthly deposit as $0.

Why use an offset sub-account calculator?

It can be tricky sometimes to understand exactly how an offset sub-account works, as well as how much you could potentially save. Our calculator helps borrowers see the benefits in a quick and simple way. In particular, borrowers can:

  • See how much sooner you can pay off your mortgage
  • Work out how much interest you can save on your home loan.


An offset sub-account is a sub-account which is linked to your home loan where you can put money (e.g. from savings or your pay) and rather than earn credit interest on that money, you use the money to reduce the interest payable on your home loan.

You are able to redraw your money anytime you want, using your Visa debit card attached to the account.

The amount in your offset sub-account is offset against your loan balance and interest is only charged on the difference.

For example, if your loan amount is $350,000 and you have $50,000 in your offset, then you will only be charged interest on $300,000. Because you pay less in interest, an offset can help you pay off your mortgage sooner while still having the ability to access the money you have in your account.

An offset can be a great way to save thousands of dollars in interest on your home loan. But it's still important to weigh up your individual circumstances to determine if it is right for you.

To get the greatest benefits of an offset sub-account, the amount of money held must be consistently at a reasonable level.

To maximise the amount that is held in your offset sub-account, many people deposit all their salary into it. They can then spend the money using a linked Visa debit card, just as they would with a transaction account.

1. Pay your salary directly into your offset sub-account

Every dollar in your the account saves you money every day on interest. So to boost your savings, have your salary paid directly into your into your account.

2. Throw in any savings

If you're saving for a holiday, new car or even school fees, you can use those savings to help pay off your home loan faster. Deposit them in your account until you need the money so you will pay less interest.

Why choose us? is an award-winning online lender that is proudly Australian and based in the heart of Brisbane, with offices in other capital cities.


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Our Awards

We’re efficient. For the last 10 years, we’ve won awards each year for our innovation, low rate home loans and car loans and extras like our offset sub-account from experts like RateCity, Canstar and Mozo to name a few. View all awards

Rate City Gold Award 2021 Best Variable Home Loan
Rate City Gold Award 2021 Best Investor Home Loan
Rate City Gold Award 2021 Best Refinance Home Loan
Outstanding Value Canstar Award 2022 Investment Variable Home Lender
Mozo Experts Choice Award 2021 Low Cost Home Loan
Mozo Experts Choice Award 2021 Offset Home Loan

Ready to get started?

Whether you’re ready to buy your first property and start repaying your home loan or you’ve owned your property for a while and want to add an offset sub-account to your loan to pay it off sooner and save in interest, we have the tools and tips to help.

Next steps


I'm buying my next home

We can help with low rate home loans for your next home.


I'm refinancing

Ready to get a lower rate home loan? We’re here to help you start saving thousands and can help you add an offset to your next loan.


I'm buying my first home

Time to enter the property market? Let us help you get the keys to your first home.


I'm building a home

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Important things to know

Length of Month
All months are assumed to be of equal length. In reality, many home loans accrue on a daily basis leading to a varying number of days' interest dependent on the number of days in the particular month.

Number of Weeks & Fortnights in a Year
One year is assumed to contain exactly 52 weeks or 26 fortnights.

Repayment Amounts
Repayments are rounded to the nearest cent. Repayments are calculated assuming a principal and interest repayment over the loan term. Weekly and fortnightly loan repayment amounts are assumed to be a quarter and a half of the monthly repayment amount respectively.

Interest Rate, Offset Balance, and Net Offset Deposit
The interest rate, starting offset balance, and net offset deposit are considered to be the same for the duration of the loan.

Offset Account
A facility whereby:
The facility operates in conjunction with a loan; Interest is calculated daily and applied monthly in arrears; and The facility has the equivalent interest rate to that of the loan and operates in such a way that the interest payable on the loan is reduced by the amount of the interest that would have been earned on the facility.

Use of the Offset Account
The calculator compares a loan operating without an Offset Account against a loan linked with an Offset Account.

Potential Interest Saved Calculated as to the sum of A = B less C, where:
A = Potential Interest Saved
B = Interest debited on loans where the loan stands alone.
C = Interest debited on loans where the loan has a linked Offset Account incorporating the offset balance and net offset deposit input by the user.

Calculations are estimates and provided for illustrative purposes only. They do not take into account any ongoing fees. The information produced by the calculator is not an indication of nor is it intended to predict future interest rates, future income, or future offset account balance. The calculator is not intended to be relied on for the purposes of making a decision in relation to a financial product and that you should consider obtaining advice from a financial services licensee before making any financial decisions. The calculator utilises information supplied by the user and assumptions made by the calculator to provide a guide only.