Investment Property Calculator

Cash flow is the money that goes in and out of your pocket each year because you own the property. There are two versions worth knowing: before tax and after tax.

Pre-tax cash flow is rent received minus loan interest minus running costs. If the answer is negative, the property is negatively geared. If it is positive, it is positively geared.

After-tax cash flow adjusts for tax. A rental loss is deducted from your other income, such as your salary, so you pay less tax. A rental profit is added to your income, so you pay more. The calculator works this out by comparing your tax with and without the property, using 2026-27 resident rates and the 2% Medicare levy.

• Annual rent = weekly rent x 52
• Interest = loan amount (price minus deposit) x interest rate
• Pre-tax cash flow = rent - interest - expenses
• Tax impact = tax on (salary + pre-tax cash flow) - tax on salary alone
• After-tax cash flow = pre-tax cash flow - tax impact, and the weekly figure is that divided by 52

On the income side it is mostly rent. Include any other money the tenant pays you, such as bond money you keep for damage or insurance payouts for lost rent.

On the cost side, the biggest item is usually loan interest. The Annual expenses box should hold everything else you pay each year: council and water rates, strata levies, landlord insurance, property management fees, land tax, repairs and maintenance, and advertising for tenants. These are all normally deductible in the year you pay them.

Some things cost you cash but are not deductible straight away, or at all. Loan principal repayments are never deductible. Stamp duty and other purchase costs form part of the property's cost base for capital gains tax instead. Travel to inspect a residential rental has not been deductible since 1 July 2017.

The tax saving from a rental loss depends on your marginal tax rate. In 2026-27 the resident rates are 15% from $18,201, 30% from $45,001, 37% from $135,001 and 45% above $190,000, plus the 2% Medicare levy.

Take the same property from the example above: a $12,400 loss before tax. On a $110,000 salary the loss stays inside the 30% bracket, so you get back 32 cents in the dollar: $3,968. It costs you $8,432 a year, about $162 a week.

On a $180,000 salary the loss is taken off income taxed at 37% plus Medicare, so the tax saving rises to $4,836. The property now costs $7,564 a year, about $145 a week.

Either way you are still out of pocket. Negative gearing reduces a loss; it does not turn it into a profit. The strategy only pays off if the property's value grows by more than the after-tax losses you fund along the way.

The calculator is built for a quick, honest cash flow estimate. It assumes an interest-only loan for a full year, a property rented every week of the year, and resident tax rates for the year you pick.

It does not include depreciation or capital works deductions. These are paper deductions: they lower your tax without costing cash each year, so leaving them out makes the after-tax result look slightly worse than it may be. As a rough guide, each $1,000 of extra deductions is worth your marginal rate in tax, for example $320 at the 30% rate plus Medicare. A quantity surveyor's depreciation schedule tells you what you can claim.

It also leaves out principal repayments, vacancy, one-off costs like stamp duty and loan setup fees, rent and rate rises over time, and capital growth. If your loan is principal and interest, your real cash outlay each week will be higher than the figure shown. To check the purchase side, use the stamp duty calculator and the borrowing power calculator.

The first stage of the changes announced in the May 2026 Budget is now law, and some details (including exactly what counts as a new build) are still being legislated. Under the changes, from 1 July 2027, if you bought an established home as an investment after 7:30pm AEST on 12 May 2026, a rental loss can no longer be deducted from your salary. It can only be used against income and gains from residential property, and any unused loss is carried forward to later years.

Properties you held before that time, and newly built homes, keep the current treatment. For the 2026-27 tax year the old rules still apply to everyone, which is what this calculator shows. If you are buying an established property now, run the numbers with the tax impact set aside too, because from 2027-28 your weekly cost could be the pre-tax figure, not the after-tax one.

For individuals, trusts and partnerships, the 50% capital gains tax discount is also being replaced with cost base indexation, and resident individuals will pay a minimum 30% tax on gains that build up after 1 July 2027. New builds can keep the 50% discount. Check the ATO for the detail before you buy.

• Treating the tax refund as income. It only gives back part of a loss you have already paid.
• Using the total mortgage repayment as the deduction. Only the interest is deductible, not the principal.
• Forgetting vacancies. Two empty weeks on $650 a week rent is $1,300 less income.
• Leaving out land tax, strata special levies or insurance, which can add thousands a year.
• Testing only today's rate. Try the calculator with the rate 1 or 2 percentage points higher to see how much buffer you have.
• Forgetting that rental losses still count for some tests. A net rental loss is added back when working out Division 293 tax on super contributions.