Capital Gains Tax Explained: How Investment Gains Are Taxed in the UK

Capital Gains Tax may apply when an individual sells or disposes of an asset that has increased in value.

The tax is usually calculated based on the gain made, rather than the total value of the asset.

For example, if an investment was purchased for £10,000 and later sold for £15,000, the gain would be £5,000.

Depending on allowances and tax rules, some or all of that gain may be subject to capital gains tax.

Capital gains tax may apply to several types of assets.

Examples include:

• Shares or investment funds
• Property that is not a primary residence
• Valuable personal possessions
• Certain business assets

However, not all assets are treated the same way for tax purposes.

For example, investments held within tax-efficient accounts such as ISAs are typically protected from capital gains tax.

Our article on tax efficient investing in the UK: ISAs, pensions and allowances explained explains how these structures may affect taxation.

The UK tax system includes a capital gains tax allowance, which allows individuals to realise a certain amount of gains each year before CGT may apply.

If total gains remain below this allowance, capital gains tax may not be payable.

HMRC publishes updated CGT allowance thresholds each tax year.

Investors often consider capital gains tax when reviewing how investments are structured.

For example, investment portfolios may be held across different account types such as:

• ISAs
• General investment accounts
• Pensions

Capital gains tax is often discussed within the broader topic of tax-efficient investing.

Understanding how gains may be taxed can help individuals better understand how investment structures affect taxation.

Our article on investment basics explained: how investing works in the UK provides a broader overview of how investments operate.