Capital Gains Tax Calculator UK 2025/26
This capital gains tax calculator works out your CGT liability for the 2025/26 tax year on shares, investments and residential property. Enter the sale price, purchase price and your annual income to see your taxable gain after the £3,000 annual exempt amount and the total CGT due. The tool applies the correct rates depending on asset type and your income tax band: 10% and 20% for shares, or 18% and 24% for residential property. Whether you are selling a buy-to-let, disposing of a share portfolio or gifting an asset, this calculator gives you a fast estimate of the tax you will owe. It is especially useful for planning disposals across tax years to make the most of your annual exemption.
Understanding Your Capital Gains Tax Results
Capital gains tax is charged on the profit you make when you sell or dispose of an asset, not on the total sale price. For 2025/26, the annual exempt amount is just £3,000, a sharp reduction from £12,300 two years ago. This means more people now face a CGT bill when selling investments or property. The rate you pay depends on two factors: the type of asset and your income tax band. Basic rate taxpayers pay 10% on shares and 18% on residential property, while higher and additional rate taxpayers pay 20% and 24% respectively. Your income determines how much of the gain falls within the basic rate band before the higher rate kicks in.
CGT Reporting Deadlines and Payment
If you sell UK residential property, you must report the gain and pay the tax within 60 days of completion using the HMRC Capital Gains Tax on UK Property service. For shares and other assets, you report through your self-assessment tax return with a payment deadline of 31 January following the end of the tax year. Failing to report within the 60-day window for property attracts penalties and interest. Full guidance on reporting requirements is available on the GOV.UK capital gains tax page.
Strategies to Reduce Your Capital Gains Tax
Timing disposals across tax years lets you use two annual exempt amounts instead of one. Transferring assets to a spouse before selling is also tax-free and effectively doubles your exemption. Holding investments inside an ISA shields all future gains from CGT entirely, making it one of the most powerful tax shelters available. If you are a company director taking dividends, our dividend tax calculator can help you model the most tax-efficient extraction strategy. For buy-to-let landlords, deducting improvement costs and selling expenses reduces the taxable gain, and principal private residence relief covers your main home. Use our take home pay calculator to see how your income level affects the CGT rate you pay.
When you dispose of an asset — selling, giving away, transferring or swapping. You do not pay when transferring to a spouse, donating to charity, or for assets in ISAs or pensions.
The annual exempt amount for 2025/26 is £3,000. It was reduced from £6,000 in 2023/24 and £12,300 in 2022/23. It cannot be carried forward.
For 2025/26, 18% for basic rate taxpayers and 24% for higher/additional rate taxpayers. These are higher than the standard 10%/20% rates for shares.
No, you do not normally pay CGT on your main home thanks to principal private residence relief. The final nine months always qualify even if you have moved out.
UK residential property: within 60 days of completion. Other assets: through self-assessment by 31 January following the tax year end.
This calculator provides estimates for guidance only. Results use 2025/26 HMRC rates. This is not financial, legal or professional advice. For regulated financial advice, speak to a qualified financial adviser.