CGT Discount Calculator AU 2025-26 (50% Rule)

What this calculator works out

This calculator estimates Australian capital gains tax (CGT) on a single asset disposal — property, shares, units, collectibles or any other CGT asset — using the 50% CGT discount for individuals and trusts who have held the asset for at least 12 months. It applies prior-year capital losses against the gross gain before the discount runs, then taxes the discounted gain at your marginal rate based on other taxable income for FY 2025-26.

The result is a general estimate, not a binding figure. CGT involves cost-base mechanics, residency rules, small business concessions and inherited-asset rules that this calculator deliberately does not model.

The formula and where the rates come from

The ATO sets out the CGT mechanics on the calculating your CGT page and the CGT discount page. The headline steps are:

1. Gross capital gain = sale proceeds − cost base.
2. Net gain = gross gain − carry-forward capital losses (and any current-year capital losses).
3. Discount = 50% × net gain, where eligible (12+ months held, individual/trust, Australian resident).
4. Assessable gain = net gain − discount, added to your other income for the year.
5. CGT = the extra tax produced by adding the assessable gain to your taxable income, at FY 2025-26 resident brackets:

Taxable income	Rate
$0 – $18,200	Nil
$18,201 – $45,000	16%
$45,001 – $135,000	30%
$135,001 – $190,000	37%
Above $190,000	45%

Companies do not get the 50% discount. Foreign-resident gains accrued from 8 May 2012 onwards are also generally not eligible.

How to read the inputs

• Sale proceeds — the contract price you received on disposal, less selling costs (agent commission, legal fees) which can also be added to the cost base.
• Cost base — purchase price + stamp duty + legal/conveyancing fees + capital improvements + eligible third-element costs (rates, interest etc. not deducted elsewhere). For property, holding costs are limited; the ATO cost-base guidance sets out the elements.
• Months held — from the day after acquisition to the day before disposal. Use the contract date for both ends.
• Prior-year capital losses — losses from earlier returns that have not yet been used. They run against the gross gain before the 50% discount.
• Other taxable income — your salary plus other ordinary income for the year. Used to pick the marginal rate that applies to the discounted gain.
• Residency / individual or trust — determines whether the 50% discount applies.

Worked examples

1. Owner-investor sells an investment property after 5 years. Proceeds $900,000, cost base $700,000. Gross gain = $200,000. No prior losses. Discounted gain = $100,000. Other income $80,000 → adding $100,000 takes income to $180,000 (37% bracket above $135k). Tax on gain ≈ $33,500. Effective rate on the underlying $200,000 gain ≈ 16.75%.

2. Share investor sells parcel after 14 months with prior losses. Proceeds $50,000, cost base $30,000. Gross gain $20,000. Prior losses $5,000 → net gain $15,000 → discounted gain $7,500. Other income $90,000 → marginal 30%. Tax on gain ≈ $2,250. Effective rate on the $20,000 gain ≈ 11.25%.

3. Crypto trader sells after 8 months. Held under 12 months — no discount. Gross gain = full inclusion. The 50% saving evaporates and the gain is taxed at the marginal rate in full. The 12-month line is the single biggest factor in the headline tax bill.

4. Foreign resident sells Australian property held 4 years. Discount blocked by post-8 May 2012 rules (assuming the asset was not held continuously since before that date). The full gain enters assessable income at non-resident rates, with no $18,200 tax-free threshold and a different bracket structure — confirm with a registered tax agent.

Common pitfalls

• Losing the 12-month clock by a few days. The discount needs ≥ 365 days of ownership. Selling the day before the anniversary halves the discount benefit.
• Forgetting third-element cost-base items. Stamp duty, legal fees, broker fees and capital improvements can all lift the cost base — and reduce the gain — when documented.
• Applying the discount before losses. The order of operations is losses first, then discount. Reversing the order over-estimates the saving.
• Treating company gains as eligible. Companies do not get the 50% discount. A discretionary trust distribution to a beneficiary often does flow through with the discount intact, but the trust itself must satisfy the 12-month and residency tests.
• Ignoring the principal place of residence (PPR) exemption. Selling your home is generally CGT-free under the main residence exemption — a different rule entirely. Investment property and second homes do not get the PPR exemption.

Related calculators

• Crypto Tax Calculator (AU) — FIFO cost basis and the 50% discount applied to crypto assets.
• Negative Gearing Calculator (AU) — model holding-year losses on a rental property.
• Property Depreciation Calculator (AU) — Division 40 / 43 deductions during ownership.
• Stamp Duty Calculator NSW — duty paid on purchase forms part of the cost base.
• SAPTO & LITO Tax Offset Calculator (AU) — offsets that may apply at retirement-age sale.

Sources:

• ATO — Capital gains tax overview
• ATO — CGT discount
• ATO — Calculating your CGT
• ATO — Working out your net capital gain or loss
• ATO — Tax rates – Australian residents