To calculate the UK capital gains tax, it is necessary to supply the following information:

• Your total capital gains for the tax year.
• The tax year, noting that this runs from 6 April in the first year to 5 April in the next.
• Whether you qualify for business tax relief on your capital gains or not.
• If you qualify for business relief, you also need to enter your lifetime capital gains reached before the tax year starts. Since this lifetime gains count dates from the first tax year of the new capital gains tax regime (2008-09), it should be kept at 0 for that tax year.

Note: This tool has been developed in line with the new capital gains tax regime, starting in the tax year 2008-09, so does not support calculations for previous tax years, where the annual income, taper relief and indexation allowance were relevant.

Associated tool link: http://www.coggit.com/tools/uk_capital_gains_tax_reckoner.html