Guidance

Work out your Capital Gains Tax adjustment for the 2024 to 2025 tax year

Use this calculator to work out the adjustment for your Self Assessment tax return for disposals of assets on or after 30 October 2024 where the rates changed.

The main rates of Capital Gains Tax for disposals of assets on or after 30 October 2024 have changed.

The rates for disposals of residential property and carried interest are unchanged.

The Self Assessment tax return will not automatically calculate at the new main rates for the 2024 to 2025 tax year.

You may need to work out an adjustment to the tax automatically calculated. You can use the adjustment calculator to do this.

You can get help with your tax return from an accountant or tax adviser. 

Who should use the calculator 

 Use the calculator if:

  • you have made a disposal of assets on or after the 30 October 2024
  • you are completing a Self Assessment tax return for the 2024 to 2025 tax year as an individual, trustee or personal representative
  • your overall capital gains are above your tax-free allowance (known as the annual exempt amount) 

If you submit your Self Assessment tax return using commercial software you need to check the correct rates are used.

Before you start 

You’ll need to work out your gains and how much tax you owe.

You should also check the:

To use the calculator to work out your Capital Gains Tax adjustment figure you’ll need:

  • date of disposal
  • amount of gains
  • taxable income
  • details of any capital losses
  • details of any pension schemes or Gift Aid payments

Calculate now

Updates to this page

Published 17 March 2025

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