Australia is set to introduce its most sweeping housing investment tax reforms since 1999, with three major changes taking effect from July 2027: restricting negative gearing deductions to capital gains rather than wages, replacing the current 50% capital gains tax (CGT) discount with an inflation-adjusted deduction, and imposing a minimum 30% CGT rate. New modelling drawing on 920,000 residential property transactions across Australia between 2007 and 2025 estimates that around 53% of investors would have paid more total tax had the reforms already been in place, while a notable 47% would have paid the same or less. The analysis found that CGT changes carry greater weight than the negative gearing adjustments, with retirees and highly leveraged investors among those likely to be hardest hit, while investors with modest capital gains could actually benefit under the new system.