By Philippa Billings, Head of Advice, Otivo
There's a bank account that earns nothing and yet can be the hardest-working money a mortgage holder owns. An offset account pays no interest at all — instead, every dollar sitting in it is subtracted from the home loan balance before interest is calculated, every single day. Owe $500,000 with $30,000 in offset, and interest is charged on $470,000. The savings arrive silently, compound over the life of the loan, and the money stays completely accessible the whole time. Here's how offsets work, what they're genuinely worth, and the two catches that decide whether one earns its keep.
An offset account is a transaction account linked to a home loan. Its balance is offset against the loan balance daily, so interest is calculated only on the difference. The money remains fully accessible for everyday use. Offset savings are effectively earned at the loan's interest rate and are tax free, though offset loans can carry higher fees or rates than basic loans.
How does an offset account actually work?
Mechanically, it's a subtraction performed daily. The lender calculates interest on the loan balance minus the offset balance, then charges that interest monthly as usual. Nothing changes about the repayment schedule — the repayment amount stays the same, but with less of it consumed by interest, more of each repayment lands on the principal. The loan shrinks faster without a single extra dollar being repaid.
The daily calculation is why offsets reward everyday behaviour, not just big balances. Salary landing in the offset on payday reduces interest from that day, even if most of it leaves again for bills over the fortnight. Households that route all income through the offset and pay expenses from it squeeze value out of money that's merely passing through.
What is money in an offset really earning?
The loan's interest rate, effectively — and with two advantages a savings account can't match.
First, the rate itself. Home loan rates almost always exceed savings account rates, so a dollar offsetting a 6 percent loan is doing more than a dollar earning 4.5 percent in savings.
Second, tax. Interest earned in a savings account is assessable income, taxed at the saver's marginal rate. Interest avoided through an offset isn't income at all — there's nothing to declare and nothing to tax. For someone on a 32 percent marginal rate, a 6 percent offset benefit is equivalent to earning roughly 8.8 percent before tax in a savings account. ASIC's MoneySmart makes the same point more plainly — offset savings are tax free.
Run the mechanism over decades and it gets substantial. A steady $30,000 offset against a 6 percent loan avoids around $1,800 of interest a year, with every avoided dollar effectively repaying principal and reducing every future year's interest in turn.
The two catches worth checking
Offsets aren't free features, and the arithmetic only works when the cost side is honest.
Catch one — price. Loans with full offset accounts often charge annual package fees or slightly higher rates than stripped-back basic loans. A $400 annual fee needs roughly $6,700 sitting in offset against a 6 percent loan just to break even. Households that would rarely hold meaningful balances may do better on a cheaper loan without one.
Catch two — the offset must be genuine. A full 100 percent offset reduces the loan balance dollar for dollar, daily. Some products offer partial offsets or offset-like features with restrictions. The product disclosure spells it out, and the difference matters.
There's also a behavioural catch that isn't in any disclosure document — an offset keeps money accessible, which is its virtue and its temptation in one. Redraw, the main alternative, holds extra repayments inside the loan where they're slightly harder to spend. Some people genuinely save more when the money has friction. Knowing which kind of person lives in the household is part of the decision.
The three-check offset review
- Check the balance habit. Average offset balance over a year, honestly estimated, is the input everything else depends on — not the best month, the average.
- Check the cost. Package fees and any rate difference against a comparable basic loan, converted to dollars per year.
- Check the alternative. Whether redraw on a cheaper loan, or simply a lower rate, would leave the household ahead of the offset's benefit at its realistic balance.
Where offset savings fit among competing priorities — other debts, super contributions, buffers — is the bigger question, and it's the one Otivo's debt module answers with regulated personal advice under AFSL and Australian Credit Licence No. 485665, weighing repayment details, income, and expenses to find effective ways to pay debt down.
Frequently asked questions
Is an offset account better than making extra repayments?
The interest saving is identical for the same dollars — the difference is access and discipline. Offset money stays in a transaction account, available instantly. Extra repayments sit inside the loan, accessible through redraw where offered, subject to the lender's conditions. Many households use both, and the better mix depends on how much accessibility genuinely matters to them.
Do offset accounts work with fixed rate loans?
Often only partially, or not at all. Full offsets are standard on variable loans, while fixed loans commonly restrict or exclude them. Borrowers who split their loan sometimes attach the offset to the variable portion for exactly this reason.
Is money in an offset account safe?
Offset accounts with authorised deposit-taking institutions are deposit accounts, covered by the Financial Claims Scheme up to $250,000 per person per institution, the same guarantee as ordinary savings accounts.
Sources
- ASIC MoneySmart — Offset accounts and redraw facilities. moneysmart.gov.au/home-loans/offset-accounts-and-redraw-facilities
- ASIC MoneySmart — Choosing a home loan. moneysmart.gov.au/home-loans/choosing-a-home-loan
- APRA — Financial Claims Scheme. apra.gov.au/financial-claims-scheme-0
Disclaimer
The information in this communication is current as at July 2026 and has been prepared by Otivo Pty Ltd ABN 47 602 457 732, AFSL and Australian Credit Licence No. 485665. This content is general information only and has been prepared without taking into account your objectives, financial situation or needs. It is not personal financial or taxation advice and should not be relied on as such. Before acting on any information, you should consider its appropriateness having regard to your personal circumstances. This material must not be reproduced in whole or in part, or posted on any social media platform, without the prior written consent of Otivo Pty Ltd.