Portfolio by Design · Investor Insights

Could your portfolio hold on one income?

Investors are asking a sharper question this spring. Not “what can I borrow?” but “what happens if one of us stops earning?” Here’s how I’d answer it, and what I check.
Published October 2026 Read time 5 min Category Investor Education

This week a couple on two tech incomes asked a room full of fellow investors whether to buy their next property or hold.

Their worry wasn’t the market. It was their jobs. One of the most useful replies told them to work out whether they could afford it on one income, just to be safe. I’d put that question first too.

The same worry is showing up across investor forums. People in tech are wondering how AI will change their roles, and what that would mean for the loans they carry. You don’t need to predict the future of work to plan for it. You need to know your numbers. If you’re weighing up your next purchase, my short readiness check is a good place to start.

What’s happening

Unemployment rose to 4.7% in September (ABS Labour Force, September 2026). Inflation ran at 4.3% over the year to September, with the trimmed mean measure the RBA watches at 3.6% (ABS CPI, September quarter 2026). The cash rate sits at 4.60% after September’s rise (CommBank Newsroom, September 2026), and the market is watching the RBA’s next meeting closely. I’ve written before about how interest rates and inflation work on a portfolio.

Unemployment, Sep 2026
4.7%
Annual inflation, Sep qtr 2026
4.3%
Cash rate, after Sep 2026
4.60%

Together they say the same thing: costs are up and incomes feel less certain. Sources: ABS Labour Force, September 2026; ABS CPI, September quarter 2026; CommBank Newsroom, September 2026.

Why it matters

Most portfolios are planned on two incomes and a bank’s assessment on a good day. The real test is a slow year. A portfolio built to last is one you can hold through a softer patch without being forced to sell at the wrong time.

What I check: the one-income test

First, the weekly holding cost. For each property, add the loan repayment, strata, council rates, insurance, management fees and an allowance for maintenance and vacancy. Take away the rent. That’s what each property asks of you every week.

Second, the buffer. How many months could you cover that gap, plus your home loan and living costs, on one income? I look for a buffer you’d be comfortable with in a slow year, not one that only works if nothing goes wrong.

Third, the loan dates. When does each fixed rate or interest-only period end? A repayment that jumps in the same year an income drops is the pressure point to plan around now. Your broker can map this with you and walk you through your finance options.

Fourth, the order of sale. If you had to sell one property, which would it be? Choose it calmly now, while you have time and choice. It’s usually the asset doing the least for your long-term plan, not the one that’s easiest to sell.

What this doesn’t mean: it doesn’t mean stop investing. It means buying at a level you could hold on one income, and keeping the rest of your borrowing capacity in reserve. Borrowing capacity and wealth aren’t the same thing.

What this means for your next decision

If the test passes, a softer market can be a good time to buy. There’s more choice, and more time to do the checks properly. If it doesn’t pass, the next move might be strengthening what you already own: building the buffer, restructuring a loan, or selling the weakest asset. That’s still progress.

Know your one-income number before you choose your next suburb.

The right team makes this easier. A good broker can run your numbers at a higher rate. Your accountant and adviser can help with structure. I’ll look at the whole portfolio with you, property by property. My finance tools are a simple first step.

Want to run the one-income test on your own portfolio?

Book your strategy session

How big should my buffer be?

It depends on your income, your loans and how secure your work is. Set it with your broker and adviser rather than using a rule from the internet. What matters is that it would carry you through a slow year without a forced sale.

Should I stop buying until rates come down?

Not necessarily. Waiting for perfect conditions can cost you time. Buy only at a level you could hold on one income, and keep a buffer in place.

What if my portfolio doesn’t pass?

Start with the weakest link: the property with the biggest weekly gap or the nearest loan change. Talk to your broker about options, then decide calmly whether to hold, restructure or sell.

Portfolio by Design · Perryn Slighting, licensed property professional · Property investment, Australia-wide.
Sources: ABS Labour Force, September 2026; ABS CPI, September quarter 2026; CommBank Newsroom, September 2026.
This article is general information only and does not constitute personal financial advice. Speak to a licensed professional about your own circumstances.