What is Capital Gains Tax (CGT)?
CGT is the tax you pay on profits from selling assets that have increased in value - like property, shares, or your business.
Current Rate (2025/26)
10%/20% for most assets; 18%/24% for residential property (2025/26)
How Capital Gains Tax (CGT) Works in Practice
Step by Step
When you sell or dispose of an asset, you calculate the gain by taking the disposal proceeds and subtracting the original acquisition cost, any allowable purchase costs (such as stamp duty or legal fees), and any enhancement expenditure (improvements that added value to the asset). If the disposal is to a connected person or is a gift, you use market value instead of actual proceeds.
You then deduct your Annual Exempt Amount of £3,000. Any applicable reliefs (such as Business Asset Disposal Relief, Private Residence Relief, or EIS deferral) are applied next. The remaining taxable gain is added on top of your income for the year to determine whether it falls within the basic-rate band or spills into the higher-rate band. The CGT rate applied depends on which band the gain falls into.
For example, if your taxable income is £40,000 and you have a £20,000 gain after the annual exemption, the first £10,270 of gain falls within the basic-rate band (up to £50,270) and is taxed at 10%. The remaining £9,730 falls into the higher-rate band and is taxed at 20%.
Practical Tips
Common Mistakes to Avoid
- Forgetting to report residential property disposals within 60 days -- HMRC charges penalties and interest on late reports
- Not using your £3,000 Annual Exempt Amount before the tax year ends -- it cannot be carried forward
- Ignoring allowable costs like stamp duty, solicitor fees, and improvement costs that reduce your taxable gain
- Assuming all property sales are exempt -- only your principal private residence qualifies for full Private Residence Relief
Frequently Asked Questions
Do I pay CGT on my main home?
Can I offset capital losses against gains?
When do I need to pay CGT?
Is transferring assets to my spouse a CGT event?
What is the CGT rate if I qualify for Business Asset Disposal Relief?
Source: HMRC Capital Gains Tax Manual (CG10000+): https://www.gov.uk/hmrc-internal-manuals/capital-gains-manual
Related Terms
Confused by accounting jargon?
AccountsOS explains everything in plain English. Ask any question about your books and get a clear, jargon-free answer.