Five Years, 1.9%: Sydney's Lost Half-Decade and the 'Property Doubles Every 10 Years' Myth

Every Sydney barbecue has someone who says it: "Just get in. Property doubles every ten years." It gets said with total confidence, and it shapes very real decisions, like how far people stretch, how thin a buffer they keep, and whether they buy at all.

So here's a number worth bringing to the next barbecue. According to Cotality's Home Value Index, Sydney dwelling values are up 1.9% over the past five years. Not 1.9% a year. 1.9% in total, from September 2021 to September 2026. Melbourne is worse: down 5.5% over five years, and still 7.5% below the record it set in March 2022.

Over the same five years, Perth rose 74%. Same country, same interest rates, completely different outcome. That gap is the real lesson.

The scoreboard nobody posts on Instagram

Cotality's latest release, covering the period to 30 September 2026, includes a table most people scroll straight past: how each city has performed over five and ten years. Here's what it says about dwelling values:

• Perth: +74.0% over five years, +97.6% over ten
• Adelaide: +59.3% over five years, +104.3% over ten
• Brisbane: +55.4% over five years, +105.3% over ten
• Hobart: +8.4% over five years, +90.2% over ten
• Canberra: +3.1% over five years, +55.8% over ten
• Sydney: +1.9% over five years, +39.5% over ten
• Melbourne: -5.5% over five years, +24.3% over ten

Look at the ten-year column. Of all eight capitals, only Brisbane and Adelaide actually doubled. Sydney's 39.5% over a decade works out to roughly 3.4% a year. To double in ten years, you need about 7% a year, every year. The rule of thumb isn't a law of nature. It's a description of a few unusually strong periods that got repeated until it sounded like physics.

What 1.9% looks like after inflation

Nominal numbers flatter. ABS figures show consumer prices rose roughly 23% between September 2021 and mid-2026. Put that next to Sydney's 1.9% and the median Sydney dwelling has lost around 17% of its value in real terms over five years. Melbourne's real decline is closer to a quarter.

And that's before holding costs. Interest, council rates, insurance, strata and maintenance all kept rising while the asset went sideways. Cotality's research director Tim Lawless put the current pressure plainly: "borrowers are far more sensitive to interest rates compared with almost fifteen years ago."

The honest caveat (because the start date matters)

In fairness to Sydney, September 2021 was mid-boom. Values had already run hard through the pandemic, so the five-year window starts from a high base. Since then Sydney has gone up, down, up again to a February 2026 peak, and is now 8.6% below that peak after six straight monthly falls. Pick a different start date and you get a different number.

That's exactly the point, though. Your returns depend heavily on when and where you buy, and on whether you can hold through the flat years. These are city-wide medians too. Individual suburbs, houses versus units, and the price tier you buy in can all land well above or below the headline. We've seen that split play out in this downturn already, with the top end of the market falling much harder than entry-level stock.

The Strategist's view: plan for flat, enjoy growth as a bonus

None of this means property is a bad asset. It means the "just get in, it'll double" logic is a dangerous way to structure a loan. Here's how I'd think about it:

• Run a zero-growth test before you buy. Ask: if this property is worth the same in five years, am I still comfortable? If the answer is no, the purchase depends on a forecast, not a plan.
• Buy holding power, not just a property. Leave headroom between what the bank will lend and what you borrow. A buffer in an offset account is what lets you ride out flat years instead of being forced to sell in one.
• Upgraders: check your real equity, not your imagined equity. If you bought in Sydney or Melbourne around 2021, your usable equity may be far lower than you assumed. Our usable equity calculator gives you a reality check before you start house-hunting.
• Investors: income matters again. With growth no longer a given and the negative gearing changes for established homes starting in July 2027, the holding cost has to make sense on its own terms.
• First home buyers: a flat market is time, not a threat. There's less pressure to rush, and buyers currently have more choice and negotiating power. Use that time to buy well rather than to buy fast. Start with your borrowing power, then work backwards to a price you can genuinely hold.

The buyers who do well over the long run usually aren't the ones who timed the boom. They're the ones who bought something they could afford to keep, then stayed solvent while time did its work.