By Philippa Billings, Head of Advice, Otivo
Picture $200 landing in your account each month with no job assigned to it. Two doors are open. Behind one, your mortgage shrinks a little faster and the interest bill with it. Behind the other, your super grows with decades of compounding ahead and a tax concession on the way in. It's one of the most common money questions in Australia, and the honest starting point is that both doors lead somewhere good — which is exactly why the choice deserves better than a coin flip. Here are the four factors that do the actual deciding.
Extra mortgage repayments deliver a guaranteed saving equal to the loan's interest rate, with the money remaining accessible through redraw or offset in many loans. Extra super contributions offer concessional tax treatment and long-term investment growth, but are preserved until a condition of release. Which suits a person depends on their interest rate, age, tax position, and need for flexibility.
What does paying extra off the mortgage actually earn?
A guaranteed, tax-free return equal to the loan's interest rate. Every dollar paid off a loan charging 6 percent stops costing 6 percent — no market risk, no waiting, no tax on the saving. Over the life of a loan, extra repayments made early can trim years off the term and remove a striking amount of interest, because they cut the principal that every future interest calculation is based on.
There's a second benefit that doesn't show up in the arithmetic — flexibility. Money paid into a loan with a redraw facility, or parked in an offset account, generally remains reachable if life changes. And a third that shows up nowhere except in people's heads — many Australians simply sleep better as the loan shrinks. That's worth something real, even if no calculator prices it.
What does putting extra into super actually earn?
Two things — a tax concession on the way in, and long-run investment growth once it's there.
Contributions made from before-tax pay, whether through salary sacrifice or a personal deductible contribution, are generally taxed at 15 percent inside super rather than at the person's marginal rate. For someone on a middle or higher tax bracket, more of each dollar goes to work than if it were received as wages. All concessional contributions — employer SG, salary sacrifice, and deductible personal contributions combined — count towards one cap, which is currently $30,000. As contribution caps can change over time through indexation or legislative changes, it's important to check the current ATO limits before making additional contributions. One caveat for higher earners belongs here — individuals whose combined income and concessional contributions exceed $250,000 pay an extra 15 percent on contributions above that threshold under Division 293, taking the rate to 30 percent, which trims the concession without eliminating it.
Then compounding does the rest. Money invested inside super has however many years remain until retirement to grow, and returns inside super are concessionally taxed too. The trade-off is preservation — the money is locked away until a condition of release, typically reaching preservation age and retiring. That lock cuts both ways. It's the discipline that makes super work, and it's also why super money can't bail out a broken hot water system.
The four factors that shape the decision
1. The interest rate.
The higher the mortgage rate, the higher the guaranteed return from repaying it. When rates are low, the case for super strengthens, since long-run investment returns have more room to exceed the loan's cost. When rates are high, the guaranteed saving becomes harder to beat.
2. Time to retirement.
The closer someone is to accessing their super, the shorter the lock-up — which is why extra contributions tend to look more attractive later in a working life, and why ASIC's MoneySmart notes that age is central to this comparison. Someone in their thirties is choosing a four-decade lock. Someone at 58 is not.
3. The tax position.
The gap between a person's marginal tax rate and super's 15 percent contributions tax is the size of the concession. A higher earner gets a bigger head start on every dollar contributed; someone on a low marginal rate gets little from the tax angle and may value flexibility more.
4. The need for a buffer.
Extra mortgage payments via offset or redraw can double as emergency savings. Super can't. A household without a rainy-day fund is usually weighing more than just returns.
Why is there no universal answer?
Because the four factors point different directions for different people — and sometimes for the same person at different ages. A 35-year-old on a high income with a big offset buffer and a 5 percent loan faces genuinely different arithmetic from a 55-year-old on an average wage with the same loan and no buffer. Both can run the numbers; neither can borrow the other's answer.
This is exactly the kind of decision Otivo's advice platform was built to work through. Its salary sacrifice module weighs income, age, retirement age, household expenses and contribution limits to assess whether directing pay into super makes sense for a specific person, while the debt module looks at repayments, income and expenses to identify effective ways to reduce debt. Both operate under Otivo's AFSL and Australian Credit Licence No. 485665, which means the answer they give is personal advice, calculated using an individual's circumstances rather than general rules of thumb.
Frequently asked questions
Is paying off the mortgage before retirement important?
Entering retirement without a mortgage is a common goal, since retirement income no longer has to service the loan, and the ASFA Retirement Standard's comfortable-retirement budgets assume home ownership without a mortgage. Some people prioritise the loan for that reason as retirement nears; others weigh it against final-years super contributions. The sequencing is personal.
Can super be used to pay off a mortgage at retirement?
Once a condition of release is met, super can generally be withdrawn and used for any purpose, including clearing a home loan. Whether that's sensible depends on the retirement income that remains afterwards — another decision where the numbers deserve to be run rather than assumed.
Does an offset account beat both options?
An offset account delivers the same interest saving as a repayment while keeping the money accessible, which is why many Australians treat it as the flexible middle path. It doesn't capture super's tax concession or investment growth, so it's a third option in the comparison rather than a winner by default.
Sources
- ASIC MoneySmart — Super vs mortgage. moneysmart.gov.au/grow-your-super/super-vs-mortgage
- ATO — Concessional contributions cap. ato.gov.au
- ASFA — Retirement Standard. superannuation.asn.au/resources/retirement-standard
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.