Capital Gains Tax Calculator Australia 2026–27

How to calculate capital gains tax in Australia, step by step

Capital gains tax is not a separate tax. It is the income tax you pay when a net capital gain is added to your taxable income. The ATO method has five steps:

• 1. Capital proceeds: usually the sale price, or the market value of what you receive if it is not money.
• 2. Cost base: what the asset cost you plus the costs of buying, owning and selling it (see below).
• 3. Capital gain or loss: proceeds minus cost base for each asset sold in the year.
• 4. Apply losses, then the discount: subtract current-year and carried-forward capital losses, then halve any remaining gain on an asset an Australian resident held for at least 12 months.
• 5. Add the net capital gain to your other income: it is taxed at your marginal rate, plus the Medicare levy.

The cost base: five elements to include

A larger cost base means a smaller gain. According to the ATO, the cost base is the sum of:

• money paid or property given for the asset
• incidental costs of buying or selling, including stamp duty, legal and conveyancing fees, agent commission, advertising, valuation fees and borrowing costs such as loan application fees
• costs of owning the asset, such as rates, land tax, insurance and interest, but only to the extent they were not deductible (for example, on vacant land)
• capital costs to increase or preserve its value, such as an extension or a rezoning application
• capital costs of defending your title to the asset

Capital gains tax on an investment property: worked example

Suppose you sell a rental property in 2026–27 for $980,000 after owning it for several years. You paid $620,000, plus $23,000 stamp duty and $2,000 legal fees, spent $35,000 on an extension, and pay $22,000 in agent and marketing costs to sell. Over the years you claimed $12,000 of capital works deductions, which the ATO requires you to subtract from the cost base.

The cost base is $690,000 and the capital gain is $290,000. After the 50% discount, $145,000 is added to your $95,000 of other income. The extra tax including Medicare is $57,750, which is 19.9% of the gain. Interest, rates and land tax you already deducted against the rent cannot go into the cost base as well.

Capital gains tax on shares and ETFs

Each parcel of shares is a separate asset with its own cost base, which includes brokerage on the purchase and the sale. Buying 2,000 shares at $12.50 and selling at $18.40, with $20 brokerage each way, gives a gain of $11,760. With $85,000 of other income, selling before the 12-month mark costs $3,763 in tax; waiting until after it costs $1,882.

The 12 months excludes both the day you bought and the day of the CGT event. If you have both discountable and non-discountable gains, apply losses to the non-discountable gains first.

Crypto tax: how CGT applies to crypto

Swapping one crypto asset for another is a CGT event, even though no Australian dollars change hands. Your capital proceeds are the market value in Australian dollars of the coin you receive. For example, if you bought crypto for $40,000 and later swapped half of your holding for another token worth $31,000, the gain on the half you disposed of is $11,000. With $70,000 of other income and less than 12 months of ownership, that adds about $3,520 to your tax.

The personal use asset exemption is narrow. A gain is ignored only if the crypto is a personal use asset and you acquired it for less than $10,000. Crypto bought and used within a short time to pay for personal items is more likely to qualify; crypto held for some time, or only partly spent, is less likely to. Crypto kept as an investment or used in a business is not a personal use asset, and the ATO looks at its main use at the time you dispose of it.

Main residence exemption and the 6-year rule

Your home is generally exempt from CGT. After you move out, you can keep treating it as your main residence indefinitely if it is not used to produce income, or for up to 6 years for each absence if you rent it out. While you do this, you cannot treat any other property as your main residence, except for up to 6 months when moving house.

If you rent it out for more than 6 years in one absence, the gain is apportioned. You are treated as having bought the property at its market value when it was first used to produce income, so get a valuation at that time. Foreign residents at the time of sale generally cannot use the exemption at all.

Timing: the contract date sets the tax year

For property, the CGT event happens on the date you sign the sale contract, not at settlement. A contract signed in June 2026 belongs in your 2025–26 return, which most people are lodging now, even if settlement was in July. Keep purchase, ownership and sale records for at least 5 years after you dispose of the property.

CGT changes from 1 July 2027

The ATO confirms that the capital gains tax and negative gearing reforms announced in the 2026–27 Budget on 12 May 2026 are now law, through the Treasury Laws Amendment (Tax Reform No. 1) Act 2026. From 1 July 2027, the 50% discount for individuals, trusts and partnerships will be replaced with cost base indexation and a 30% minimum tax rate on capital gains. The CGT changes only apply to gains that accrue after 1 July 2027.

In the same package, negative gearing for residential property investments will be limited to new builds from 1 July 2027, but properties held at the time of the announcement (7:30pm AEST on 12 May 2026) are exempt from that change. Assets sold in 2026–27 still use the current 50% discount, which is what the calculator above applies.