A price drop should make a home easier to buy. In Perth, that logic is running into a wall. Prices have come off sharply, but the monthly cost of owning has barely shifted. Higher mortgage rates are absorbing the saving before the buyer ever sees it.
That is the core of the Perth housing slump affordability problem. The sticker price is one number. The repayment is another. Buyers live on the second one.
Price is not the number that gets paid
Most people shop on price. Lenders assess on repayment. A buyer’s real constraint is how much of their income can safely go to the loan each month, and that depends on the rate as much as the purchase price.
Here is a simple illustration, not a forecast. Say a buyer borrows $600,000 over 30 years. At a 4% rate, the monthly repayment sits around $2,860. At 6%, the same loan costs roughly $3,600. That is a jump of about 25% from the rate alone.
Now work the other way. To bring a 6% repayment back down to what a 4% loan cost, the loan would need to shrink by around a fifth. So a price fall of roughly 20% is needed just to stand still on monthly cost. Anything smaller leaves the buyer worse off than before the rate rise, even though the headline price looks better.
In plain English
A fall in price only helps if it is bigger than the damage the higher rate does to your repayment.
Borrowing capacity moves the other way
There is a second squeeze, and it works against the first. Higher rates also shrink how much a lender will let someone borrow. Serviceability tests add a buffer on top of the actual rate, so a rising rate cuts capacity twice: once through the real repayment, once through the buffer.
That matters because a falling market only helps buyers who can still reach it. If a household’s borrowing power drops by roughly the same proportion as prices, the two effects cancel. The buyer has a cheaper target and a smaller budget, and ends up in the same spot. We covered how sharply this can bite in our look at which states lose hardest when borrowing capacity is cut.
The catch is that the neutralisation is rarely perfect. Where capacity falls faster than prices, buyers are locked out even as the market weakens.
The affordability paradox in practice
Economists sometimes call this the affordability paradox: cheaper prices that cost more to hold. It is not a trick of the numbers. It is what happens when the cost of money rises faster than the price of the asset falls. Our earlier piece on the affordability paradox when cheaper prices cost more walks through the mechanics in more detail.
Commentary on Perth has split along predictable lines. One camp reads a falling price as a buying window. The other points to flat repayments and says nothing has really improved. Both are describing real data. They are weighing different parts of the same equation.
Who actually gets relief
The gains are uneven, and that is where the useful signal sits.
- Buyers with large deposits or existing equity. They borrow less, so the rate bites less. They capture more of the price fall.
- Buyers stretching to the limit of capacity. They get almost nothing. Their budget fell as fast as the market did.
- Existing owners on fixed or lower legacy rates. They are insulated for now, but face a repayment reset when the fixed term ends.
- Renters saving for a deposit. A lower price lowers the deposit target, but if rents stay high, the saving rate slows.
That split is the point. A price fall is not a uniform benefit. It rewards people who already have a financial buffer and does little for those who most needed relief.
What could change this
The whole picture turns on the rate path. If rates ease meaningfully, the repayment burden drops and the price fall starts doing real work for buyers, because both levers pull the same way. If rates stay high or rise, the slump keeps looking like relief on paper and feeling like none in the budget.
There is also a supply angle. If prices fall far enough to slow new building, a later shortage could push prices back up, which would shorten the window for buyers who wait.
Treat any single-state price chart with care. It tells you where the market has been, not whether you can afford to act in it.
The rule of thumb for buyers
Before reading anything into a price fall, run your own repayment at the current rate and at a rate 2 to 3 points higher. If you can carry the higher figure, the price drop is a genuine opportunity. If you can only manage the current one, the fall is thinner relief than it looks.
For a wider view of how pricing is shifting across the market, see our analysis of the housing price forecast and what it means for equity.
Next step: stress-test your own repayment before you chase a headline price drop. Subscribe to the newsletter for the weekly signal.
General info, not financial advice.
