Should You Pay Off Your Mortgage or Invest? The Australian Answer in 2025

It's one of the most common questions we get from clients: "Should I be putting extra money into my mortgage or investing it?"

The honest answer is that it depends on your specific situation — your interest rate, your tax position, your risk tolerance and your long-term goals. But the framework for thinking about it is straightforward, and for most Australian property owners in 2025 the answer leans strongly in one direction.

The Mathematical Starting Point

The decision comes down to a simple comparison: what's the after-tax return of paying down your mortgage versus the after-tax return of investing?

Your mortgage interest rate is your guaranteed, risk-free return from paying it down. If your home loan rate is 6%, every extra dollar you put in the offset account earns you an effective 6% return — risk free, tax free (in the case of an offset account).

The question is whether you can reliably do better than 6% by investing. Historically, Australian shares have returned approximately 9-10% per annum over long periods. Investment property has similarly delivered strong long-term returns, though with more variance and higher transaction costs.

The Tax Variable

Here's where the Australian tax system changes the calculus significantly.

If you're a high-income earner in the top marginal tax bracket (47%), investment returns need to be viewed through a tax lens. The income from an investment property (rent) is taxable. Dividends from shares are taxable (though franking credits help). Capital gains are taxable (with a 50% discount after 12 months).

Meanwhile, paying down your owner-occupied mortgage gives you a guaranteed return that is effectively tax-free.

For someone in the top tax bracket, a 9% gross share return becomes roughly 4.8% after tax on income (ignoring capital growth). That's below the effective return of paying down a 6% mortgage.

But negative gearing changes this significantly. If your investment generates a tax loss (as many investment properties do in the early years), that loss offsets your taxable income — which means the government is effectively subsidising your investment. This changes the comparison materially.

The Offset Account — The Best of Both Worlds

For owner-occupied mortgages, the offset account is often the answer that bridges the gap. Money in your offset account reduces the interest you pay on your mortgage (giving you the guaranteed return of your interest rate) while remaining accessible if you need it — including for investment.

This is why the offset account strategy is so powerful: you get the guaranteed return of your mortgage rate while maintaining liquidity and optionality.

When Investing Makes More Sense

Investing typically makes more sense when: your mortgage interest rate is relatively low, you have a long time horizon (10+ years), you're in a lower tax bracket, you have access to negative gearing benefits through an investment property, and you have sufficient financial stability to absorb investment volatility.

When Paying Down the Mortgage Makes More Sense

Paying down your mortgage makes more sense when: interest rates are high relative to expected investment returns, you're approaching retirement and want to reduce risk, you carry significant non-deductible personal debt alongside your mortgage, and peace of mind and financial security are more important to you than maximising returns.

The Sabea Financial View

For most of our clients — working Australians with mortgages, in their 30s-50s, with a 10-20 year horizon — the answer is not either/or. It's both, in the right structure.

Aggressively offsetting your owner-occupied mortgage (guaranteed return) while using your equity to fund investment property or ETFs (building wealth) is the framework that underlies our Equity Mastery Program. The key is making sure the debt structure is set up correctly — separating deductible investment debt from non-deductible personal debt from day one.

Getting this right makes a material difference over 10-20 years. Getting it wrong is expensive and complicated to fix.

Book a free strategy session and we'll help you work out the right approach for your specific situation.