By Philippa Billings, Chief Advice Officer, Otivo
Pay off debt or invest is one of the most common money questions there is, and it has a deceptively clean answer hiding a messy one. On paper, you compare two numbers, the interest rate on your debt against the return you might earn investing. But one of those numbers is certain and the other is a hope, and that difference changes everything. Here's how to think it through.
Quick answer
Whether to pay off debt or invest often comes down to comparing the interest rate on your debt with the return you might earn investing. Paying off debt gives a guaranteed return equal to the interest saved, while investing returns are uncertain. As at July 2026, high-interest debts like credit cards usually favour paying down first, while low-interest debt is more finely balanced.
How do you compare paying off debt with investing?
You line up two returns. Paying off debt earns you a guaranteed return equal to the interest rate you're no longer paying, a 20% credit card rate cleared is effectively a guaranteed 20% return. Investing offers a return too, but an uncertain one that could be higher or lower and isn't promised. So the comparison isn't just rate against rate, it's a sure thing against a maybe, and that certainty carries real weight.
Why is paying off debt a guaranteed return?
Because the interest you avoid is money that stays in your pocket, no matter what markets do. If a debt charges 8% interest, paying it off saves you that 8% with certainty, which is the equivalent of a risk-free 8% return on that money. Very few investments offer a guaranteed return anywhere near that, which is what makes paying down higher-rate debt such a strong option. The higher the rate, the more compelling the guaranteed saving becomes.
When does paying off debt usually win?
When the debt is expensive. High-interest debts such as credit cards and many personal loans typically charge rates well above what investing can reliably return, so clearing them first is usually the stronger move. The guaranteed saving from eliminating a high rate is hard for uncertain investment returns to beat. For most people carrying costly debt, paying it down is the clearer, lower-risk path.
When might investing make sense instead?
When the debt is cheap and the horizon is long. If your only debt is a low-rate mortgage, the guaranteed saving from extra repayments is smaller, and over a long timeframe investing, including inside tax-advantaged super, may offer a higher expected return, though never a guaranteed one. This is the genuinely balanced zone where reasonable people land differently, and where your own circumstances and comfort with risk matter most.
What else matters besides the numbers?
Plenty. Your tolerance for risk shapes how much you value certainty over potential upside. An emergency buffer matters, since being debt-focused with no cash reserve can backfire when the unexpected hits. And there's peace of mind, some people simply sleep better with less debt, and that's a legitimate factor even when the maths is close. The numbers start the conversation, but they rarely finish it alone.
Frequently asked questions
Is it better to pay off debt or invest?
It depends on comparing your debt's interest rate with the return you might earn investing, and on your comfort with risk. High-interest debt usually favours paying down first, since its guaranteed saving typically beats uncertain investment returns.
Should I pay off my mortgage or invest?
This is the finely balanced case, because mortgage rates are lower than high-interest debt. Over a long horizon, investing may offer a higher expected return, but paying down the mortgage is a certain saving. Circumstances and risk comfort decide it.
Should I invest while I have credit card debt?
Usually clearing high-interest credit card debt comes first, because its guaranteed cost typically exceeds what investing can reliably return. Paying down that debt is effectively a risk-free return at the card's interest rate.
Where to from here
The right answer depends on your rates, your goals and your appetite for risk. Otivo, a licensed Australian financial advice platform holding AFSL and Australian Credit Licence No. 485665, offers a debt advice module that helps you find effective ways to pay down debt while covering essentials, based on your debts, income and expenses. It helps you weigh the guaranteed saving against your other goals.
Sources
- ASIC MoneySmart — pay off debt or save and invest — moneysmart.gov.au
- Australian Taxation Office — tax on investments and super — ato.gov.au
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.