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The SA108 form is a supplementary page which sometimes needs to be submitted alongside the paper-based Self Assessment tax return by people reporting capital gains.

Do I need to submit an SA108 form?

Should I complete an SA108 if I do my Self Assessment online?

How do I submit an SA108 form?

If you submit your main Self Assessment tax return using the paper based SA100 form and you need to tell HMRC about any capital gains or losses which you made during the tax year, you may need to include an SA108 form with your return.

Capital gains are the profit that you make when you ‘dispose’ of an asset. This usually means that you’ve sold it, but disposing of an asset can also mean that you’ve gifted it to someone else, swapped it, or been compensated for it another way.

You’ll need to include the details in your tax return if you made a disposal of assets worth more than £49,200 (in the 2022/23 tax year), or if the gains you made were more than the annual exempt amount.

The annual exempt amount is a tax-free allowance for capital gains. You’ll start paying Capital Gains Tax if the total gains you make in a year are above the allowance threshold. The annual thresholds are shown in the table below.

Individuals Trustees
2022/23 £12,300 £6,150
2023/24 £6,000 £3,000
2024/25 £3,000 £1,500

No, you’ll only need to complete and submit the SA108 form to report Capital Gains Tax if you use the paper-based version of the Self Assessment return. When you complete your tax return online, you’ll be asked a series of questions to tailor your return so that it includes all of the sections that you need.

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You’ll need to download the SA108 form from the HMRC website – make sure you use the correct form for the tax year that you’re reporting!

Once it’s complete, submit it along with your main tax return form and any other supplementary pages to the address shown on the main form.
Learn more about our online accounting services, including support for your Self Assessment. Call 020 3355 4047 and get an instant online quote.

About The Author

Elizabeth Hughes

A content writer specialising in business, finance, software, and beyond. I'm a wordsmith with a penchant for puns and making complex subjects accessible. Learn more about Elizabeth.

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