Capital Gains Tax Calculator - property, 2026 rules

Your capital gain is the sale proceeds (after selling costs) minus your cost base - the purchase price plus buying costs like transfer duty and legals, reduced by any Division 43 capital works you claimed. Under the enacted 2026 reform the gain is then split at 1 July 2027: the part accrued before that date keeps the old 50% discount treatment (held 12+ months), while the part accruing after it uses CPI indexation of the cost base plus a 30% minimum tax rate. Only first-owner new builds keep the 50% discount for the later gains. The taxable amount is added to your income and taxed at your marginal rate, topped up to the 30% floor where it applies.

For gains accruing from 1 July 2027 the 50% CGT discount is replaced by CPI indexation plus a 30% minimum tax - and that applies to every asset and every owner, grandfathered or not. The law deems each asset sold and re-acquired at 1 July 2027, banking the gain to that date under the old discount rules until you actually sell. The one exception is first-owner new builds, which keep the 50% discount for later gains with the option to choose indexation instead. Future CPI is unknowable, so this calculator uses a 2.5% a year CPI-proxy assumption - confirm the detail with your accountant.

Only for the gain accrued to 1 July 2027. Grandfathering protects negative gearing, not the CGT discount: the deemed sale at 1 July 2027 banks the earlier gain at the 50% discount, and everything the property gains after that date is taxed under CPI indexation plus the 30% minimum tax, the same as an established purchase.

A floor on the tax on indexed gains accruing from 1 July 2027. The basic income tax on the gain - excluding the Medicare levy - is worked out as the top slice of your taxable income; if it falls short of 30% of the gain, extra tax makes up the gap, rounded down to the whole dollar. It does not apply to banked pre-July-2027 gains or to new-build gains taken at the 50% discount, and the law exempts recipients of listed income-support payments.

Yes - that is the release valve of the reform. Carried-forward quarantined losses that were never absorbed by rental income are applied against residential capital gains at sale: the law offsets them against the banked pre-July-2027 slice first, then the indexed slice, before the discount is taken - and never against non-residential gains. On a heavily negatively geared post-reform property, the pool can offset a substantial slice of the gain.

Yes - the reform does not touch it. If the property was your main residence first, the exemption covers your occupancy years, and the 6-year absence rule can extend it after you move out and rent the property, provided you do not claim another main residence in that period.

Division 43 capital works deductions reduce your cost base - you effectively got the deduction along the way, so it comes back into the gain at sale. It is usually still worth claiming (a deduction now versus a discounted or deferred cost later), but it surprises sellers who skip it in their CGT estimate.