How much profit should you make flipping a house in Australia?

How much profit should you make flipping a house in Australia? There isn't a single national number, and anyone who quotes you one is guessing. The honest answer is that your target profit is whatever leaves you a real buffer after every cost the deal can throw at you — including tax — and you set that number before you buy, not after. Profit isn't what the property "should" make. It's what's left when the reno runs long, the sale comes in a fraction under your estimate, and the tax office treats the gain as income. This post is about picking a target margin that survives all of that, and working backwards from it to the most you can pay.

It's general information, not financial advice, and the figures below are illustrative ranges to show the method — not a forecast for your deal.

The margin-on-cost benchmark

The first mistake is measuring profit against the sale price. "I bought at $600k and sold at $700k, that's a $100k flip" ignores the $60k–$80k of stamp duty, renovation, holding and selling costs that sat in the middle. Measure your margin against total project cost instead — every dollar in, from the purchase price and stamp duty through to the agent's commission on the way out. That's the number that tells you whether the deal is actually worth the risk.

There's no official benchmark for what that margin should be, but the working rule most flippers use is a net margin — before tax — somewhere in the mid-teens to low-twenties as a percentage of total cost. Below about 10% you're doing a lot of work and carrying a lot of risk for a return a term deposit could rival without the stress. The reason for the buffer is simple: a flip has more ways to go wrong than to go right, and the margin is what absorbs the ones that go wrong.

Two things quietly eat that margin in Australia specifically. Selling costs are real money — agent commission runs from the low-2% range in the big metro markets up toward 2.5%–3%+ in regional areas, plus GST on top (PropertyNow's 2026 state-by-state figures). And a genuine flip is almost always taxed as ordinary income, not a capital gain, so the 50% CGT discount doesn't apply — the ATO's revenue-versus-capital treatment means your headline profit gets taxed at your marginal rate. Target your margin on the after-tax number, or at least know what the pre-tax figure becomes once the ATO takes its cut. This is also why the US 70% rule doesn't translate cleanly to Australia: our stamp duty and income-tax treatment eat into the buffer that rule assumes.

Why thin margins kill

A thin margin isn't a smaller win. It's a coin flip. Here's why, with round illustrative numbers.

Say your all-in cost is about $600k and you expect to sell at $700k. On paper that's a $100k profit before tax, or roughly 17% on cost — a healthy deal. Now let three ordinary things happen at once, none of them a disaster. The renovation runs 15% over budget on an $80k scope: there's $12k gone. The project takes two months longer than planned, so add holding costs — interest, rates, insurance, utilities — of maybe $2k–$3k a month: another $5k. And the market softens slightly, so the sale lands 3% under your after-repair estimate: that's $21k off the top. You've just lost close to $38k of a $100k margin, and you haven't been unlucky — you've been normal.

Now run the same three knocks against a deal you bought thinner, expecting $50k on $600k. The exact same ordinary overruns don't dent your profit — they erase it, and then some. That's the whole point. A fat margin turns a bad month into a smaller win; a thin one turns it into a loss. The margin is your insurance policy against the reno, the calendar and the market all being slightly worse than you hoped, which is the base case, not the worst case.

This is exactly what the flip ROI calculator is for — not to admire the profit in the good scenario, but to stress-test it. Push the reno cost up 15%, add two months of holding, drop the sale price a few percent, and see whether there's still a deal. If a small, realistic set of knocks wipes the profit out, the margin was never big enough. The full cost breakdown of a flip walks through every bucket those knocks land in.

Profit vs annualised return

A dollar figure on its own can flatter a bad deal. $50k profit sounds identical whether it took you four months or fourteen — but it isn't. Annualise it and the picture changes completely: $50k in four months is running at roughly $150k a year on that capital; the same $50k dragged out over fourteen months is barely $43k a year, and you carried the risk and the holding costs three times as long to get there.

So the target isn't only "how much profit" — it's "how much, over how long, for how much of my money at risk". Two levers matter. Time, because every extra month is another month of holding costs bleeding the margin and another month your capital can't do anything else. And your cost of capital — if the deal's annualised return doesn't comfortably beat your loan rate and what the money would earn elsewhere, the profit isn't compensating you for the work and the risk. A smaller, faster flip that annualises well can be a better use of your money than a bigger, slower one that ties you up. Judge the deal on the annualised return, then sense-check the raw dollars are worth getting out of bed for.

What the deal score treats as "enough"

This is the shift that changes how you buy: stop asking "how much will this make?" and start asking "what's the most I can pay and still hit my target margin?" Those are the same question asked from opposite ends, and the second one is the one that protects you.

That inversion is the core of how FlipPro works. Every full analysis runs the numbers for the strategies a property can support, applies the real costs — stamp duty, reno, holding, selling, tax — and lands on the one figure that matters: the maximum you should pay for that property, for that strategy, to leave a margin worth having. The deal score reflects whether the numbers clear that bar with a buffer, not whether they scrape over the line in a perfect world. You can see the whole thing worked through end to end in the sample analysis — including the Penrith deal that looked fine on the surface and would have lost around $500k, which is the best argument I know for setting your margin before you fall in love with a property.

If you want to see how the strategies stack up against each other on a single address, that's what the full analysis is built to do — so "enough profit" becomes a price you either get, or a property you walk away from.

So, how much profit should you make flipping a house in Australia?

Enough that a normal run of overruns still leaves you paid for your work and your risk, which in practice means targeting a net margin in the mid-teens or better on total cost, judged on an annualised basis and after tax. Pick that target first. Then work backwards to the highest price that still delivers it, and treat that price as a ceiling, not a starting point.

The discipline is boring and it's the whole game: decide the margin, calculate the max buy, and walk when the deal can't hit it. Run your own numbers in the flip ROI calculator, and when you're ready to have the strategy, the costs and the max-buy figured for you on a real address, that's what FlipPro is priced to do — from browsing for free to a full analysis in minutes.

This is general information only and not financial, tax or investment advice. Margins, costs and tax treatment vary by deal, structure and market, and the figures here are illustrative ranges chosen to demonstrate the method. Confirm your own numbers and speak to a qualified accountant about how a flip will be taxed in your circumstances before you commit.

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