Anyone who has tried working through the Inland Revenue matching rules for share trades will know that the process can quickly become very complicated for even a modest number of trades. The 30 day rule especially can cause unexpected gains/losses. The purpose of this site is to help UK tax payers to calculate, and to keep track of, their capital gain (or loss) based on their share trades. This is important for effective tax planning and can potentially save you a significant amount on your tax bill.
To use the capital gains calculator simply store your trades in a spreadsheet, or a simple text editor like Notepad, in a simple format. If you use an online stockbroker then check the conversion utilities for a suitable converter. Also note that rights issues and transfers to spouse are supported. See the FAQ for frequently asked questions.
Note this calculator can now also extract the current share prices (delayed by 20 minutes) of your current portfolio entries and display a running total of your current chargeable gain/loss for the current tax year. Select the live portfolio display option to enable. Also to view a bar chart showing the breakdown per stock of gains/losses over a tax year click the View Chart button.
This calculator is updated every tax year and is fully up to date for the 2017-2018 tax year.