Computation and Foreign tax

These two tabs provide a computation of the gains and losses and allow for the input of foreign tax information. For Help on the other areas within Capital Gains click on the links below:


This tab displays a Capital Gains computation based on the disposals entered for the year. If you have not entered any disposals for the year then the computation will show only a zero gain.

Downloading the computation,

You can download a PDF copy of the computation by clicking on the Download PDF button. You can also download a copy from the Review & File tab for the Tax return after you have prepared the tax return for filing.

Including the computation with the tax return,

There are three options available, selected from a drop-down list alongside the question ‘Are you attaching a computation with this tax return?’  

  • NO – Not required’ No computation will be attached
  • YES – Auto-attach this computation’ Taxfiler will automatically attach its computation to the tax return
  • ‘YES – I have attached my own’ Use this option if you are attaching your own computation. You will need to attach the computation manually from the data input tab

Foreign Tax Credit & SWT:

  • Foreign Tax Credit Relief and Special Withholding Tax

Use this tab to enter details of foreign tax and SWT for CGT purposes. See HMRC help sheet-hs263-self-assessment for more information.

  • Amount of chargeable gain under UK rules’ enter the amount of gain that would be payable if the UK CGT rules were used to calculate the gain
  • Foreign tax paid’ enter the foreign tax paid on the disposal
    • Total Foreign Tax Credit Relief on gains’ enter the foreign tax credit relief claimed
    • Special Withholding Tax’ enter any UK tax withheld.

Useful Resources

A simple guide to Capital Gains Tax