Around 2.5 million investment properties face CGT valuation choice, Opteon says

About 2.5 million Australian investment properties could require individual valuations ahead of capital gains tax changes taking effect on 1 July 2027, according to property valuation firm Opteon.

The estimate spans roughly 2.3 million residential properties alongside 250,000 commercial and agribusiness properties.

Opteon managing director for Australia and New Zealand Scott Chapman said the Australian Taxation Office's proposed apportionment method applies an even formula across an entire ownership period, which may work against owners if price growth was concentrated in earlier years.

“If a property experienced most of its growth before July 2027 and then enters a flatter period, that formula may attribute more of the gain to the period after the changes take effect,” Mr Chapman said. “For some investors, that could result in a significantly higher tax outcome than using a property-specific valuation that reflects what the property was actually worth at the transition date.”

In one scenario modelled by Opteon, a Hawthorn property owner saved an estimated $22,000 in capital gains tax by securing an independent valuation rather than relying on the ATO formula.

Opteon recorded a 30 per cent increase in enquiries in July. The firm noted that investor demand has softened across metropolitan markets including Sydney and Melbourne, while regional markets and parts of Western Australia, Queensland and South Australia have stayed firmer.

According to Opteon's July 2026 Property Pulse Check, Melbourne dwelling values fell 2.6 per cent over the June quarter, while Perth rose 23.9 per cent over the year to June.