Capital Gains Tax Calculator

Capital Gains Tax Calculator

📌 Important: This calculator is for guidance only and does not constitute personal tax advice. It assumes no other gains, losses, or reliefs and uses the 2025/26 tax rules. Tax rules may change, and your circumstances could affect your actual tax. If unsure, speak to an adviser.
  • Use your allowance wisely: Everyone gets a £3,000 CGT allowance this year. Selling smartly to stay within that limit can help avoid tax.
  • Use a tax wrapper: Moving investments into a Stocks & Shares ISA or pension (SIPP) can shelter future growth from CGT — but moving them might trigger a gain now.
  • Use your partner’s allowance: If you're married or in a civil partnership, you can transfer assets to your partner to make use of both allowances.
  • Lower your income: CGT rates depend on your income band. Lowering income (e.g. via pension contributions) may reduce your tax rate.
  • Use past losses: You can offset CGT with losses from this or past years — even from up to 4 years ago.

Usually, it’s the person selling or gifting the asset. There’s normally no CGT when gifting to your spouse or a registered charity. If the asset is jointly owned, you only pay tax on your share of the gain.

You’re only taxed on gains above the £3,000 allowance. The gain is what you sold the asset for minus what you paid.

Your CGT rate depends on how much income you earn and whether the asset is residential property.