An offset account sounds straightforward: keep money in an account linked to your home loan and pay less mortgage interest.
The part that deserves closer attention is whether the savings are actually large enough to justify the loan’s interest rate, package fees or account fees.
For Australian borrowers considering an offset account in Australia, the useful question is therefore not simply, “Does an offset account save interest?” It is: “How much money will I realistically keep in the account, what will that save me, and what will the feature cost?”
Understanding those numbers can make it easier to compare home loan options without being distracted by features you may rarely use.
Quick Overview
An offset account is generally a transaction account linked to a home loan. Instead of earning interest on the money in the account, its balance reduces the portion of the mortgage on which the lender calculates interest.
For example, if your mortgage balance is $500,000 and you keep $40,000 in a linked offset account, interest may be calculated as though the relevant loan balance were $460,000.
Because home loan interest is commonly calculated daily, the amount sitting in the offset account from day to day matters.
An offset account may provide greater value when you maintain a meaningful balance for long periods. It can provide less value when the balance is usually low or when the offset-enabled loan carries additional fees or a higher interest rate.
An offset account is also different from redraw. Offset money remains in a separate transaction account, whereas redraw generally involves accessing additional repayments that have already been made against the loan.
Before choosing either feature, compare the interest rate, fees, access conditions and how you expect to use your money.
How Does an Offset Account Work?
A mortgage offset account is linked to your home loan but operates separately from the loan itself.
Depending on the product, you may be able to use it much like an ordinary transaction account. Your salary might be paid into it, bills might come out of it and everyday purchases may be made from it.
The important difference is what happens when your lender calculates mortgage interest.
ASIC’s Moneysmart explains that the amount held in the offset account reduces the loan balance used to calculate interest. Interest on most Australian home loans is calculated daily, so generally the more money you keep in the offset account, and the longer it remains there, the greater the potential interest saving.
Suppose you have:
| Item | Amount |
|---|---|
| Home loan balance | $500,000 |
| Offset account balance | $40,000 |
| Balance used for interest calculation | $460,000 |
You still owe $500,000. The $40,000 has not been paid off the mortgage. It remains in your offset account.
Its benefit is that, while it remains there and the account is operating as intended, it reduces the amount on which mortgage interest is calculated.
When Does an Offset Account Actually Reduce Mortgage Interest?
An offset account starts producing a benefit when there is money in the correctly linked account and that balance is being recognised by the lender for interest calculations.
The size of the saving depends primarily on three things: your offset balance, your home loan interest rate and how long you maintain that balance.
Consider a simplified example.
Assume a homeowner maintains an average of $40,000 in an offset account for an entire year and their mortgage rate is 6% per annum.
A rough calculation would be:
$40,000 × 6% = $2,400
That suggests approximately $2,400 less interest over the year, before considering changing daily balances, repayments, rate changes, fees and the lender’s actual interest calculation method.
The 6% figure here is purely illustrative. It is not presented as a current or recommended home loan rate.
If the average offset balance were only $5,000 at the same illustrative rate, the simple annual interest reduction would be approximately $300.
That difference is important.
An offset account can be useful without necessarily being valuable enough to justify paying substantially more for the loan.
The Average Balance Matters More Than the Highest Balance
It can be tempting to look at the largest amount you expect to have in your offset account.
Suppose you occasionally have $30,000 in the account after being paid, but regular mortgage payments, groceries, utilities and other expenses quickly reduce it to $5,000.
Your savings will not be based on having $30,000 in the account for the entire month.
Because mortgage interest is generally calculated daily, the changing balance matters.
This is why someone who consistently keeps $40,000 or $50,000 available may receive substantially more benefit from an offset account than someone whose balance regularly falls close to zero.
The practical question is:
How much will probably remain in the account on an ordinary day?
That figure is usually more useful than your best-case balance.
Offset Account Versus Redraw
Offset accounts and redraw facilities can both reduce the interest cost of a home loan, but they do it differently.
| Offset account | Redraw facility |
|---|---|
| Money is held in a separate linked account | Money generally comes from additional repayments made into the loan |
| The offset balance reduces the amount used to calculate interest | Extra repayments reduce the outstanding loan balance |
| May operate like an everyday transaction account | Access depends on the lender’s redraw conditions |
| Money has not been paid directly against the loan principal | Money has already been paid into the loan |
| May involve additional account, package or loan costs | May have withdrawal limits, fees or other restrictions |
Moneysmart notes that some lenders may limit how much can be redrawn, charge a fee or delay access. The exact conditions depend on the loan.
Neither feature should automatically be assumed to be better.
If easy day-to-day access to savings is important, an offset account may have advantages.
If you mainly want to make extra repayments and are comfortable with the lender’s redraw conditions, redraw may meet that need without requiring a more expensive home loan package.
The comparison should be based on the specific loan rather than the feature’s name.
A Tax Difference Worth Knowing About
Offset and redraw can also have different consequences where a property is, or may later become, income-producing.
The Australian Taxation Office treats amounts redrawn from a loan as further borrowing, with the tax treatment of interest depending on how those redrawn funds are used. Using an investment loan redraw for private purposes, for example, can create a loan containing both income-producing and private components.
That can become complicated quickly.
Anyone considering turning a former home into an investment property, borrowing for investment purposes or mixing personal and investment debt should obtain appropriate tax advice before moving substantial amounts between a mortgage, redraw facility and offset account.
When Might an Offset Account Be Worth Considering?
There is no universal balance at which an offset account becomes “worth it”.
It depends on what you would pay for the feature.
Imagine Loan A includes an offset account but costs $395 more each year through fees than a comparable loan without one.
If your offset account is expected to save only $250 of mortgage interest during the year, you could be worse off overall despite technically paying less interest.
If it saves $2,000 while adding $395 in costs, the calculation looks quite different.
Moneysmart recommends comparing the interest rate on an offset-enabled loan with alternatives, as well as checking annual package fees and monthly account fees.
This is why comparing loans only by their advertised interest rate — or only by their list of features — can be misleading.
You need to consider both.
Fees and Account Rules to Check
Before deciding whether the feature has practical value, check the loan documentation rather than assuming all offset accounts work identically.
A useful checklist is:
- Is the account definitely linked to the correct home loan?
- What interest rate applies to the offset-enabled loan?
- Could you obtain a lower rate without the offset feature?
- Is there an annual package fee?
- Does the offset account have a monthly fee?
- Which part of the loan does the offset apply to if the loan is split?
- Are there transaction or access restrictions?
- What happens to the offset arrangement if you refinance or change loan products?
- How will you confirm that the offset balance is actually reducing interest?
- How does the total cost compare with using a redraw facility instead?
The answers give you something more useful than simply asking whether the lender “offers offset”.
Check That Your Offset Is Actually Connected
This is an easy detail to overlook.
In 2026, ASIC reported problems involving banks failing to properly set up, monitor or manage some mortgage offset accounts. ASIC said customers could pay more interest than intended when an account was not correctly linked to the mortgage. It also warned that refinancing or switching loan products could sometimes disrupt the link between an offset account and the loan.
That creates a simple practical task for borrowers.
Check your banking app, loan statement or online banking information to confirm that the offset account is linked to the correct loan.
If you cannot tell how the lender is recognising the offset balance, ask the lender to explain it.
It is particularly worth checking after refinancing or changing loan products.
Does an Offset Account Reduce Your Mortgage Repayment?
Not necessarily.
An offset account primarily affects how much interest is calculated rather than automatically reducing the contractual repayment you are required to make.
If your repayment remains unchanged while less of it is needed to cover interest, a greater proportion can effectively go towards reducing the principal.
Over time, that may help reduce the total interest cost and potentially shorten the period required to repay the mortgage, depending on the loan structure and how the account is used.
That distinction matters because “saving interest” and “lowering this month’s required repayment” are not necessarily the same thing.
Questions to Ask Before Choosing an Offset Loan
Instead of beginning with, “Which loan has an offset account?”, start with the financial impact.
Ask your lender or mortgage broker to show what the same borrowing amount would look like with and without the feature.
Then estimate a realistic average offset balance.
For example, someone with $60,000 permanently available may reach a very different conclusion from someone expecting to maintain $2,000 after normal monthly spending.
Also consider whether the money needs to remain easily accessible.
Some borrowers value having emergency savings available in a transaction account while still reducing their mortgage interest. Others may prefer putting additional money directly into their loan and relying on redraw.
There is no need to pay for flexibility you are unlikely to use.
A Simple Way to Compare the Potential Benefit
For an initial estimate, you can use:
Average offset balance × home loan interest rate = approximate annual interest reduction
For example:
$25,000 × 5.5% = approximately $1,375
Then compare that estimated saving against any additional annual fees and any difference between the interest rate on the offset loan and a comparable alternative.
Remember that this is only a rough comparison.
Actual mortgage interest calculations are affected by daily balances, changing loan balances, rate changes and the lender’s contractual method of calculation.
Frequently Asked Questions
Does money in an offset account earn interest?
Generally, the benefit of the money is that it reduces the mortgage balance used for calculating interest rather than earning savings-account interest. Moneysmart describes the benefit as paying less interest on the home loan.
Can I withdraw money from an offset account?
An offset account generally operates as a transaction account, so access can be considerably more flexible than money paid directly into a loan. Check the specific account conditions because products can differ.
Is an offset account the same as making extra mortgage repayments?
No. Money in an offset account remains in a separate account. An extra repayment is paid into the loan and reduces the loan balance itself.
Is redraw the same as offset?
No. Redraw usually allows you to access eligible additional repayments previously made into the home loan. Access may be subject to lender rules, limits or fees. An offset account is a separate account linked to the mortgage.
How much money do I need in an offset account for it to be worthwhile?
There is no fixed amount. Compare the interest you expect the average balance to save against any additional fees and any higher interest rate attached to the loan.
Should I keep all my savings in an offset account?
That depends on your financial circumstances, liquidity needs, loan conditions and other financial objectives. The fact that an offset account can reduce mortgage interest does not automatically mean every available dollar should be kept there.
What to Do Next
If you already have an offset account, check that it is linked correctly and review the average balance you actually maintain rather than focusing on occasional peaks.
If you are comparing new home loans, calculate the approximate annual saving from your likely offset balance and then compare it with the complete cost of the offset-enabled loan.
The key question is not whether offset accounts work. When correctly linked, they can reduce the mortgage balance used to calculate interest.
The more useful question is whether your expected interest saving is greater than the additional cost of having the feature.
That is the calculation worth making before you choose.
General Information Disclaimer
This article provides general educational information only and does not constitute financial, tax or legal advice. Home loan products, fees, lending conditions and individual circumstances vary. Consider the relevant product documents and obtain qualified financial, tax or legal advice where appropriate before making decisions about your mortgage.
