A 20% Housing Downturn Would Reset Melbourne to 2017

Cotality has modelled what a housing downturn would do to every Australian capital, and the deepest scenario on its list would rewind Melbourne's median dwelling value to where it sat in June 2017 — roughly $675,000. Sydney comes off slightly better in time terms: a 20 per cent fall would take the median back to about $1.05 million, its level in May 2021.

The analysis steps through falls of 5, 10, 15 and 20 per cent and asks one question: how many years of gains does each one erase? Cotality research head Gerard Burg was blunt about the purpose. "This isn't a forecast of what we expect to happen," he said. It's a stress test, the kind banks run to find the weak points.

It lands at an awkward moment. Cotality's national Home Value Index fell 0.7 per cent in July, the sharpest single month since December 2022. Sydney dropped 1.4 per cent, Melbourne 1.2 per cent, and both now sit more than 5 per cent below their peaks. The first rung of that ladder is already under our feet.

Where a Housing Downturn Bites Hardest

The pattern in the numbers is counterintuitive. The cities with the biggest price tags have the furthest to fall in years, not just dollars, because their recent gains have been thin. The cities everyone worried about overheating banked so much growth so fast that even a savage fall barely scratches the surface.

Sydney and Melbourne go back years

Melbourne has been the national laggard for a long stretch, so a 20 per cent fall doesn't just clip a boom — it unwinds close to a decade of movement. Sydney's worst case lands in the middle of the pandemic surge, wiping out the 2021 run-up. Anyone who bought in either city since 2022 would be looking at a number smaller than the one on their loan contract.

The mid-sized capitals barely blink

Brisbane, Perth and Adelaide would only be pushed back to around April 2024 at the earliest, even under the harshest scenario. Two years of gains gone, everything before that untouched. Burg's read on those markets was direct:

If you've been a home owner in any of those mid-sized capitals for an extended period of time, you're actually in a very strong position to withstand a pullback.

Why 20 Per Cent Is a Stress Test, Not a Forecast

Burg points out that the worst national decline in 40 years was 8.2 per cent. That period includes the 2022 rate shock, when the Reserve Bank lifted the cash rate at the fastest pace in a generation and values still didn't fall by a tenth. A housing downturn of 20 per cent would be unprecedented in modern Australian records, which is precisely why it sits at the top of the range rather than the middle.

For scale: the ABS puts the value of Australia's residential dwellings above $10 trillion. A 10 per cent fall would erase roughly $1 trillion of household wealth on paper — but paper is the operative word. It only turns into real money when someone sells, refinances, or has a valuer walk through the door.

What the Market Is Actually Doing

The falls are concentrated at the top end. Over the three months to July, upper-quartile values dropped 3.2 per cent while the cheapest quarter of the market edged up 0.3 per cent. Perth still rose 0.1 per cent in July and Adelaide slipped only 0.2 per cent. This looks like a premium-end correction spreading outward, not a broad collapse.

The regions have turned too. The combined regional index fell 0.2 per cent in July, its first decline since January 2023, with regional NSW, Victoria and Queensland all negative. Regional SA and WA are the holdouts. Capital city listings now sit 5.7 per cent above the five-year average, which means more stock, more choice and far less urgency for buyers.

The Buyers a 5 Per Cent Fall Could Hurt

Cotality has flagged negative equity risk for recent buyers with small deposits, including those using the federal 5 per cent deposit scheme. The arithmetic is unforgiving. Put $50,000 down on a $1 million home and a 5 per cent slide — the mildest scenario modelled — takes it to $950,000. Add agent fees and moving costs and you're selling at a loss.

The comfort is that a housing downturn only bites if you're forced to sell. Cotality puts mortgage arrears near 1.45 per cent, below the 1.69 per cent peak recorded in mid-2024 when rates sat at similar levels. Cotality's Tim Lawless has argued arrears are unlikely to spike, given a strong labour market and the three-percentage-point buffer lenders apply when testing your loan.

What to Watch Over the Next Few Months

Follow listing volumes in your own suburb rather than the national headline. Capitals and regions are moving in opposite directions right now, and so are price brackets inside the same city. If stock keeps building through spring, negotiating power stays with buyers.

If you own, work out your loan-to-value ratio before you need it — a falling valuation can quietly kill a refinance even when your repayments are perfectly fine. If you're buying, a softer market is a reason to negotiate harder, not to stretch further. And if you got in recently on a slim deposit, build a cash buffer and give yourself the option of sitting tight for a couple of years. That's the whole difference between a paper loss and a real one.