The 1% rule offers a quick test for finding profitable properties. Search "1% rule property investing" and the same test comes back everywhere: a rental property should charge at least 1% of its purchase price in rent each month. It sounds like a sensible filter. Run it on Australian capital city property and it eliminates essentially everything, and that is not a sign your shortlist is wrong. It is the rule hitting a market it was never calibrated for.
This guide covers what the rule actually says, why the arithmetic breaks down in Australia, what it hides even when a property passes, and what to run in its place. It also covers the 80/20 rule, the other slogan you will keep meeting, and what kind of tool that one actually is.
What the 1% rule says
The rule is a rent-to-price screen. Monthly rent should be at least 1% of the purchase price, so a property bought for $500,000 would need $5,000 a month in gross rent. Written as a formula: monthly rent ≥ purchase price ÷ 100.
The point is speed. It is a quick first pass on one question: would the rent cover the mortgage and leave you breaking even or better? It has been around for years precisely because it is quick. It is also only a screener. It ignores maintenance, insurance, taxes and every other cost of holding the property, which is why it is generally treated as a pre-screening or short-listing tool and nothing more.
Why the arithmetic breaks in Australia
The rule asks for 1% of the purchase price each month, which works out to 12% of the price across a year. Property Update puts gross rental yields, rent measured before costs, at 2.5% to 4% a year for houses and 3.5% to 5% for units across most Australian capital cities, with regional properties stretching to 5% to 6% and sometimes higher. Set those numbers against the 12% the rule demands and the rule does not rank properties in most capital cities. It disqualifies them.
Sydney shows the mechanism clearly. Domain's report flags Sydney's vacancy rate tightening to a record low of 0.8% in March 2026, yet rents holding flat rather than accelerating, because affordability rather than demand is the binding constraint. When rents are capped by what tenants can pay and prices are not, yields stay low. A benchmark of 12% was never built for that.
What the rule hides even when a property passes
Suppose a property clears the bar. The rule measures gross rent, and gross rent is not money you keep. Property Update suggests expecting around 40% of gross rent to disappear into running costs such as maintenance, property management, insurance, rates and vacancies before a single dollar of mortgage repayment. A property can pass the 1% test and still bleed cash.
The rule is also silent on growth, and growth is where Australian investing has actually made its money. The suburbs with the strongest long-term capital growth often have the lowest yields, and the pattern runs deep: high-growth properties tend to sit at the more expensive, negatively geared end of the market, while high-yield ones are cheaper and positively geared. The tax data backs this up. In 2012/13, just under two-thirds of Australian investors declared a net rental loss, claiming the tax benefits of negative gearing. The rent-covers-everything benchmark was never how most of the market ran; Australian investors have tended to rely on long-term price appreciation rather than chasing high rental yields.
None of this is getting easier to shortcut. In the 2026 Federal Budget, delivered on 12 May, the government announced changes to both negative gearing and capital gains tax, and until the final legislation passes, the exact impact on after-tax returns stays uncertain. A rent-to-price ratio cannot price any of that. Stress-testing your numbers under more than one scenario can.
What about the 80/20 rule?
The 80/20 rule borrows from the Pareto principle: roughly 80% of your investment success comes from 20% of your decisions, with the right location, property type and financing structure doing most of the work. Unlike the 1% rule, it does not hand you a number to test a property against. It is a prioritisation principle, not a filter. The 1% rule fails because it pretends one calculation can carry a whole decision. The 80/20 rule makes the opposite point: the decision is the work, and most of it sits in choosing where and what to buy.
What to run instead
No single threshold replaces the 1% rule, because the job it was doing, condensing a decision into one number, is the problem. The work splits into three layers.
Pick the strategy first. Yield, growth or a blend: the choice decides which suburbs are even candidates. The investors who do well in Sydney pick the strategy, filter suburbs against real data and resist paying up for premium postcodes the market has already priced to perfection.
Then filter suburbs on data that matches the strategy. Sydney is not one market but dozens of micro-markets with different price points, rental yields, growth trajectories and risk profiles. Our guide to Sydney's suburbs, yields and growth corridors breaks down where prices sit, what rents and vacancy are doing and which corridors are drawing infrastructure spending.
Then run the property's full numbers. Start from gross rent, take off roughly 40% for running costs, subtract the mortgage, and hold the result up against more than one tax and rate scenario while the 2026 changes are still settling. A property that survives that stack is a candidate. A property that only passes the 1% test has passed a test that was never calibrated to this market.
It also helps to know that nobody else is checking this for you. Almost 10% of Australians invest in property, and a Senate inquiry found no specific laws protecting them from bad property investment advice. Rules of thumb thrive in exactly that space.
Where PropSpotter fits
Rules of thumb are what fills the gap when research feels out of reach. PropSpotter's system is built to close that gap with the research itself: institutional-grade suburb research, an automated property sourcing engine and one-on-one coaching from an experienced investor, for a fixed $4,990. There is no percentage-based fee that grows with the purchase price; whether you are buying at $500K or $1.2M, the price is the same. No per-session billing, no upsells. The three stages, Research, Source and Coach, are designed to leave you with the skills, so the next decision is one you can run yourself.