How capital gains tax is calculated on disposals made on or after 30 October 2024

For disposals of assets, other than residential property or carried interest, made on or after 30 October 2024, the rates on which Capital Gains Tax (CGT) is charged increased from 10% and 20% to 18% and 24% respectively. HMRC have specified that the automatically generated calculation of Capital Gains Tax liability will not include the increase in tax liability arising because of these changes in rates. Instead, a separate adjustment to the original rates will be calculated.

This means that the tax calculation summary (SA02) will display the original rates of tax on the gain but will also be required to include and display an adjustment to take account of the increased rates, for the amount of taxable gain arising on or after 30 October 2024. The adjustment box CGT51 will be used for this purpose.

How do I ensure the correct amount of capital gains tax is calculated in TaxCalc?

SimpleStep

When entering assets details for disposals (Capital Gains Tax > Asset Details), if the disposal date entered is on or after 30 October 2024, TaxCalc will automatically populate the correct boxes in the CGT pages and calculate the adjustment required for box CGT51.

HMRC Forms 

When entering gains in the CGT pages you will need to specify how much of the gains included in boxes CGT13.4, CGT17, CGT18, CGT26, CGT34, CGT49, CGT50 and CGT52.2 relate to disposals made on or after 30 October 2024 by entering amounts in the corresponding boxes CGT13.4a, CGT17a, CGT18a, CGT26a, CGT34a, CGT49a, CGT50a and CGT52.2a to ensure that the required adjustment is calculated.

For both modes a summary report is produced which provides workings for the calculation of the adjustment. We recommend reviewing the summary, which can be found in Summaries > CG Adjustment Summary,  to ensure entries made are correct.