What this number actually tells you

Cashflow is the number that decides whether you can hold a property long enough to make money from it. Not the rent. Not the loan repayment on its own. The weekly gap between what comes in and what goes out, after tax.

Get it wrong and you're the person force-selling in year three because the holding cost crept up while you weren't looking – usually right when the market's flat and it's the worst possible time to sell. Get it right and you know exactly what you're signing up for before you sign.

How the numbers are worked out

The logic is simple, even if the admin isn't:

→ Start with your gross rent, then knock off a couple of weeks for vacancy. No property is tenanted 52 weeks a year forever.

→ Take out the running costs – council rates, water, insurance, property management, strata if it's a unit, and a maintenance buffer.

→ Take out the loan cost. If you're interest-only, that's the interest. If you're principal and interest, you pay the full repayment but only the interest is deductible – the calculator splits that for you, because the tax office does too.

→ That gives you your pre-tax position. If it's negative, the loss can reduce your taxable income, which generates a refund at your marginal rate. Add depreciation – a deduction you claim without spending a cent – and the refund gets bigger.

Pre-tax cost, minus the tax refund, divided by 52. That's your real weekly number.

The 2027 change most calculators are still pretending doesn't exist

Here's the part you need to pay attention to, because nearly every cashflow calculator online is quietly giving you a number that's about to be wrong.

Negative gearing is changing. It's not a rumour or a budget thought bubble – it's legislated. The Treasury Laws Amendment (Tax Reform No. 1) Bill 2026 passed Parliament and was enacted on 26 June 2026, and it takes effect from 1 July 2027.

What it does, in plain English:

→ If you buy an established home after 7:30pm on 12 May 2026, you can offset the rental loss against your salary only until 30 June 2027. After that, the loss is quarantined – you can still carry it forward against future rental income or the eventual capital gain, but you can't use it to shrink your wage this year.

→ If you already held the property before that date, nothing changes. You're grandfathered.

→ If you buy a genuine new build, negative gearing stays. That's the carve-out, and it's deliberately narrow – a knock-down-rebuild that replaces one house with one house won't count. It has to actually add supply.

So a calculator that shows you a healthy after-tax cost off the back of a fat negative gearing refund might be describing a benefit you won't have in two years. This one lets you pick your situation and shows both numbers – before and after the change – so you're not planning your cashflow around a deduction with an expiry date.

(The precise definition of a "new residential dwelling" is still being finalised in a legislative instrument, so if you're buying new specifically for the tax treatment, that's a conversation for your accountant before you commit.)

Positive or negative – neither one is automatically the smart move

Negative cashflow means the property costs you money week to week, and you're wearing that in exchange for growth and tax benefits. Positive cashflow means the rent and refund cover the costs, usually in exchange for slower growth.

There's no trophy for either. A high-income earner chasing a strong growth market often runs slightly negative on purpose. Someone closer to retirement, or on a single income, usually wants the property paying its own way. The right answer depends on your income, your borrowing capacity, and what you actually want the property to do. The calculator gives you the number – what you do with it is strategy.

The three things that quietly wreck a cashflow forecast

→ Vacancy. Most calculators assume the place is rented every week of the year. It won't be. Two weeks empty on a $600 property is $1,200 gone before you've paid a single bill. This one counts it by default.

→ Rate moves. Today's rate isn't tomorrow's rate. With the cash rate at 4.35%, plenty of investors have already felt this. The stress test shows what your weekly number looks like if your rate climbs one or two per cent – run it before you buy, not after.

→ Depreciation you can't actually claim. New builds throw off serious depreciation. But if you buy an established property, you generally can't claim the plant and equipment (the carpets, blinds, aircon) – that door closed on second-hand assets back in 2017. Spreadsheets routinely plug in a new-build depreciation figure on an old house and flatter the result. Use a quantity surveyor's schedule for the real number.

Where we come in

A cashflow figure tells you whether a property is affordable to hold. It doesn't tell you whether it's worth buying.

That's the bit we do. Premier Buyers works with investors only, right across the country, and the difference is the lens – 14 years inside institutional finance before this, so we read the numbers and the legislation rather than react to the headlines. We check the things a calculator can't see: the building, the street, the tenant demand, whether the growth story holds, and how you get out when the time comes.

If the numbers stack up on a property you're looking at, that's exactly the point to have a proper conversation.

Book a discovery call

Frequently asked questions

What is property cashflow?
It's the difference between the rent you collect and everything it costs to own the property – loan interest, rates, insurance, management, maintenance – adjusted for tax. Positive cashflow means the property pays for itself. Negative means it costs you to hold.

How does negative gearing affect my tax?
When a property runs at a loss, that loss can reduce your taxable income and generate a refund at your marginal rate. On a $10,000 loss at a 37% marginal rate, that's roughly $3,700 back – though from 1 July 2027, whether you can offset it against your salary depends on when and what you bought. Confirm your position with your accountant.

Does the 2027 negative gearing change affect me?
Only if you buy an established property after 12 May 2026. Properties held before then are grandfathered, and eligible new builds keep negative gearing. The calculator lets you model each case.

Interest-only or principal and interest for cashflow?
Interest-only gives you lower repayments and a higher deductible portion, which helps weekly cashflow. Principal and interest costs more but builds equity. Many investors start interest-only and switch later. The calculator handles both.

Is this financial advice?
No. It's a general information tool to help you understand the numbers. It doesn't account for your personal circumstances and isn't tax, credit or financial advice. Talk to a licensed professional before acting.