CGT on shares calculator
CGT on shares calculator: enter what a parcel cost with the brokerage you paid, what it sold for with the brokerage that came off, and the two trade dates. The calculator below returns the capital gain, the 50% discount when the parcel clears 12 months, and the tax at your marginal rate.
Capital gains tax on shares in Australia is the same federal capital gains tax that covers property and every other asset. No share-specific rate exists, and no state adds one. The holding period and the income the net gain lands on decide the bill.
How it works
How capital gains tax on shares works in Australia
The gain on a sale of shares is the net proceeds minus the cost base. The cost base is the purchase price plus the brokerage paid on the buy, and the brokerage on the sale comes off the proceeds. Both fees work for you: the buy fee raises the cost base and the sell fee lowers the proceeds.
Hold the parcel 12 months or more and the CGT discount removes 50% of the gain before tax. The count excludes both the day you acquired the parcel and the day of the sale, so a parcel bought on 1 April first qualifies on 2 April the following year. For shares, the CGT event falls on the date of the trade contract, not on the settlement date.
Capital losses are netted off before any discount. A loss on one parcel cuts the gain on another in the same return, and whatever is left carries forward to later years. A loss never touches the tax on your salary, and the discount never applies to a net loss.
Worked example
One parcel held a year and a half: $24,000 gain, $3,840 tax
You buy $16,000 of shares on 10 March 2025 and pay $20 of brokerage. On 24 September 2026 you sell the lot for $40,040 with $20 of brokerage again. The cost base is $16,020, the net proceeds are $40,020, and the capital gain is $24,000.
Held for 18 months and two weeks, the parcel clears the 12-month test with room to spare. The 50% discount removes $12,000, leaving $12,000 of net capital gain for the return. On a salary of $70,000 the gain sits wholly inside the 30% bracket, so the tax on the gain is $3,840, and $240 of that is Medicare levy.
One share disposal in the 2026-27 income year
| Step | Amount |
|---|---|
| Sale price | $40,040 |
| Sale brokerage | −$20 |
| Net proceeds | $40,020 |
| Purchase price | $16,000 |
| Buy brokerage, inside the cost base | $20 |
| Cost base | $16,020 |
| Capital gain | $24,000 |
| CGT discount (50%) | −$12,000 |
| Net capital gain added to income | $12,000 |
| Tax on the gain at $70,000 income, Medicare included | $3,840 |
Common traps
Where the sums go wrong
Most errors come from treating a parcel as a ticker rather than a set of buys. One ticker is many parcels, each with its own date, its own cost and its own slice of the sale.
- Averaging the holding period across parcels. Every parcel carries its own dates. The calculator matches each sale to the parcels it came from and tests the 12 months parcel by parcel.
- Entering the settlement date. The CGT event is the contract date of the trade. Type that date, not the day the money landed.
- Dropping the buy-side brokerage. It belongs in the cost base next to the price, and leaving it out overstates the gain by the fee.
- Discounting each gain before netting losses. Losses come off first across the year, and the discount applies to what survives.
- Treating dividends as part of the gain. Dividends are income in the year they are paid, and a dividend reinvestment plan buys separate parcels, each with its own date and cost.
Questions
Frequently asked questions
How is CGT on shares calculated in Australia?
Net proceeds minus cost base. The cost base is the purchase price plus buy brokerage, and the sale brokerage comes off the proceeds. Held 12 months or more, the 50% discount applies, and the net gain joins your income at your marginal rate with the Medicare levy on top.
Does brokerage reduce the capital gain?
Yes, on both ends. Buying brokerage joins the purchase price in the cost base, and selling brokerage reduces the proceeds. Both fees trim the gain.
How long do I hold shares to get the 50% discount?
Past 12 full months, with the acquisition day and the sale day both excluded from the count. The test runs per parcel, not across the portfolio.
Can losses on shares cut the tax on my salary?
No. Capital losses offset capital gains only. A year with losses and no gains adds nothing to your income, and the losses carry forward to later years.
Which date counts as the sale date?
The contract date. A sale under contract is a CGT event on the day the contract is made, not on settlement.
What does the calculator need for each parcel?
Two dates, two prices and the brokerage on each side. Enter those for every buy and every sell, and the rest is arithmetic.
Sources
Where these figures come from
Also on capitalgainstax.net