How to use the Capital Gains Tax Calculator
- 1 Enter your gain: the sale price minus what you paid and allowable costs such as fees and improvements.
- 2 Enter any allowable losses from other disposals.
- 3 Enter your other taxable income, such as salary, for the tax year.
- 4 Choose Business Asset Disposal Relief if it applies, then read the tax due.
Worked example
A £30,000 gain on shares with a £40,000 salary. After the £3,000 exempt amount, £27,000 is taxable. Taxable income is £27,430, leaving £10,270 of basic rate band, which is taxed at 18% (£1,848.60). The other £16,730 is taxed at 24% (£4,015.20), so CGT is £5,863.80.
Features
2026/27 rates
18% on gains within the basic rate band and 24% above, for property, shares and other assets.
Annual exempt amount
The first £3,000 of net gains each tax year is tax-free.
Business Asset Disposal Relief
A flat 18% from 6 April 2026 on qualifying business disposals, up to a £1 million lifetime limit.
Band split
See how much of the gain is taxed at each rate.
When to use it
Selling shares
Work out tax on shares held outside an ISA or pension.
Second homes and buy-to-let
Estimate the tax before you agree a sale price.
Timing a sale
See whether selling in a year with lower income saves tax.
Selling a business
Compare tax with and without Business Asset Disposal Relief.
Frequently asked questions
What are the CGT rates for 2026/27?
18% for gains that fall within your unused basic rate band and 24% for gains above it. The same rates apply to residential property, shares and most other assets.
What is the annual exempt amount?
£3,000 for individuals and £1,500 for most trusts. Only net gains above it are taxed.
Do I pay CGT on my home?
Usually not. Private Residence Relief covers your main home if you lived in it throughout ownership and the garden is not over half a hectare.
How is the rate decided?
Gains are added on top of your taxable income. The part that fits in the basic rate band, up to £50,270 of total income, is taxed at 18% and the rest at 24%.
When do I pay?
For UK residential property you must report and pay within 60 days of completion. Other gains are reported through Self Assessment by 31 January after the tax year.
What is Business Asset Disposal Relief?
A relief for people selling all or part of a business, or shares in their own trading company, that cuts the rate to 18% in 2026/27 on up to £1 million of lifetime gains.
Can losses reduce my bill?
Yes. Losses in the same year are set against gains first, and unused losses reported to HMRC can be carried forward to later years.
Results are estimates based on the official rates linked above. Confirm important figures with the issuing authority or a qualified adviser before you act on them.
Reviewed by ToolsUnlocked Team · Last updated