GlenCalc

UK Capital Gains Tax calculator

Enter your total gains for the tax year and your taxable income (income minus your Personal Allowance). Your home is usually exempt.

Your answer

Capital Gains Tax£3,060.00
Gains above the allowance£17,000.00
Taxed at 18%£17,000.00
Taxed at 24%£0.00
  • Deduct allowable costs and losses before entering the gain. Business Asset Disposal Relief and gains in trusts have other rates.

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How we worked it out

Updated as you change the numbers.

  1. Gains after the £3,000 allowance: £17,000.00.
  2. £17,000.00 fits in the rest of the basic rate band (£37,700 − £20,000.00) at 18%; £0.00 above it at 24%. Tax = £3,060.00.

Method and assumptions

GOV.UK: tax-free allowance £3,000; from 6 April 2026 gains are taxed at 18% when, added to taxable income, they fall within the basic rate band, and at 24% above it.

Questions

How much CGT on a £20,000 gain with £20,000 of taxable income?

£3,060: £17,000 above the allowance, all within the basic rate band at 18%.

Sources

Method and figures checked on November 2, 2026. Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.

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