Calculator
Capital gain on a share sale
Enter one purchase and one sale. The tool shows the gain, then the Finance Act 2025 rate for someone on the Active Taxpayers List and for someone who is not. Holding period and the buy date decide the rate. This is one trade, not NCCPL’s yearly net.
How the arithmetic works
Proceeds are the sale price times quantity. Cost is the buy price times quantity plus the buy fees you enter. Gain is proceeds minus sell fees minus that cost. If the gain is negative, the estimate of tax at a positive rate is zero in this simple tool. Real loss treatment is a question for your adviser, not a minus sign we invent rules for.
A partial sale that closes several lots is not this form. Use the FIFO comparison, or the app’s lot book, when the shares you sold were bought on more than one date.
Worked illustration
Five hundred shares bought at 100 with 200 in buy charges, sold at 130 with 250 in sell charges: proceeds 65,000, cost 50,200, gain 14,550. If those shares were bought on 1 August 2024, the schedule’s rate is 15% on the Active Taxpayers List and 30% off it. Shares bought on or after 1 July 2025 are 15% either way.
Common questions
Why do the two rates differ?
For shares bought before 1 July 2025, someone off the Active Taxpayers List is often charged more. Shares bought on or after that date are 15% in this schedule either way. A later Finance Act can change the table.
Does this match NCCPL?
Not necessarily. NCCPL has the official computation. This is personal arithmetic so you can see the gain before that computation.
Where do fees go?
Buy fees sit in cost. Sell fees reduce proceeds. Leaving them out makes the gain look larger than the contract notes.