From 1 July 2027, one classification decides the tax treatment of your next investment property: whether it counts as a new build. Which properties clear that bar comes down to the new build definition in the 2026 negative gearing rules.
The word "new" is doing less work than you would expect. Negative gearing is the ability to offset a rental loss against your other income, and the test the reform is built around is not whether a dwelling is new. It is whether the dwelling adds to supply. A house that is brand new in every ordinary sense can still miss: the explanatory material points at exactly this case, demolishing one house and building one in its place, where net supply is unchanged.
The final definition sits in a legislative instrument that is still being settled, so this guide gives the tests as they currently stand and flags the points the drafting has not yet locked. It does not cover how each side of the line is taxed.
The Act and the start date
The reform is law, not a proposal. The Treasury Laws Amendment (Tax Reform No. 1) Act 2026, a Commonwealth Act, passed both Houses on 25 June 2026 and received Royal Assent the following day, as Act No. 49 of 2026. The substantive changes do not start immediately: the property measures take effect from 1 July 2027, which gives investors a defined window to work out how the reform applies to property they already hold or are considering buying.
The test is 'additional', not 'new'
The definition is the part still moving. It is not written in the Act itself: the definition of a new residential dwelling is being prescribed by legislative instrument, which gives the government flexibility to adjust it without returning to Parliament. A second tranche of legislation covering exactly this point, along with the housing investment exemptions, went to consultation with submissions closing on 21 August 2026. Anyone making a ten-year decision today is doing so against a rule that is not fully locked.
On the working tests as they stand, four things decide whether a dwelling qualifies.
Who sells it to you. The purchase is from the builder or developer, not from a previous owner-occupier or investor.
What was on the site. Broadly, a dwelling built on vacant land, or one created by demolishing an existing property and replacing it with more dwellings than were there before. The one-for-one version is expected to fail: the explanatory material indicates that demolishing one house and building one house in its place would not qualify, because net supply is unchanged. New is not the test. Additional is the test.
Whether anyone has lived in it. The dwelling has not previously been occupied, or has not been occupied beyond a short qualifying period understood to be around twelve months.
Whether it has been sold as a home before. It cannot have been previously sold as a home. The first buyer from the developer holds a new residential dwelling; the person who buys it from them in five years does not, and the status is expected to be lost on that subsequent sale.
Getting the classification wrong does not just cost you a deduction each year; it changes the tax outcome on exit.
Two more sit in the open basket. A substantial renovation is the clearest case: a renovated dwelling is an improved dwelling, not an additional one, and there is no indication renovation will be treated as creating new supply for these purposes. Whether off-the-plan purchases, substantial renovations or conversions qualify at all depends on drafting that has not yet been confirmed.
Where PropSpotter fits
Every one of those tests is a research question, and each one is answerable before you commit to a purchase. That is the stage PropSpotter works on.
The research stage produces a suburb research brief built from 30+ data sources, plus a personalised investment strategy for your budget. The sourcing stage runs a proprietary listing system that monitors your target suburbs 24/7, screens for bushfire risk, public housing and owner-occupier ratios, and delivers qualified listings to you. The coaching stage puts you in a dedicated WhatsApp group with your advisor from sourcing through to settlement, negotiation coaching and due diligence support included, with a trusted contact network of property managers, mortgage brokers and building and pest inspectors behind it.
Nobody buys the property for you; you stay in control of every decision. The design is deliberate: after settlement you have a research brief, the knowledge and the confidence to do it again independently. The system covers every Australian state, so the process works the same whether you are in Sydney looking at Brisbane or in Melbourne exploring Perth. It costs $4,990. Our own comparison with a buyer's agent, who runs the research, sourcing, negotiation and purchase for you, puts that full-service route at $15,000 to $25,000 or more for a single purchase.
Timing is worth a thought in this window. From your strategy session to receiving your research brief is typically 2-3 weeks, and most clients go from first call to settlement within 2-4 months. Set that against the 1 July 2027 commencement date when you are planning a purchase.
If you want a read on where you stand, the entry point is a free 30-minute strategy call, no obligation. Bring a rough idea of your budget or borrowing capacity, any suburbs or markets you have been considering, and as many questions as you like. If you would rather ask in writing first, it is hello@propspotter.com.au.