Report and pay Capital Gains Tax

You can report Capital Gains Tax you need to pay:

  • using the Capital Gains Tax on UK property service within 30 days of selling UK property
  • straight away using the ‘real time’ Capital Gains Tax service
  • annually in a Self Assessment tax return

If you have to send a Self Assessment return for another reason, you must include capital gains on your return, even if you’ve already reported and paid them.

Before you report

You’ll need:

  • calculations for each capital gain or loss you report
  • information from your records about the costs and what you received (the ‘proceeds’) for each asset
  • any other relevant details, such as any reliefs you’re entitled to

If you have sold property in the UK

If you sold your property after 6 April 2020 you must report and pay Capital Gains Tax within 30 days of selling property in the UK.

You may have to pay interest and a penalty if you do not report gains on property within the time limit.

You’ll need a Government Gateway user ID and password. If you do not have a user ID, you can create one when you report and pay.

If you sold the property before 6 April 2020, report the gain using the ‘real time’ Capital Gains Tax service or in your next Self Assessment tax return.

If you’re not resident in the UK

If you’re a non-resident and you’ve sold property or land in the UK, tell HM Revenue and Customs (HMRC) within 30 days, even if you have no tax to pay.

Report gains and pay straight away

If you’re a UK resident you can use the ‘real time’ Capital Gains Tax service to report any gains that are not from selling UK residential property.

You’ll need a Government Gateway user ID and password. If you do not have a user ID, you can create one when you report and pay.

When you use the service you’ll need to upload PDF or JPG files showing how your capital gains and Capital Gains Tax were calculated.

When to report

You can use the ‘real-time’ service as soon as you’ve calculated your gains and the tax you owe. You do not need to wait until the end of the tax year.

You must report by 31 December after the tax year when you had the gains.

The tax year runs from 6 April to 5 April the following year.

After you’ve reported your gains, HMRC will send you a letter or email giving you a payment reference number and telling you ways to pay.

Do not pay your Capital Gains Tax bill until you’ve received your payment reference number.

Change your report

If you need to change your report, you’ll need your report reference number starting with ‘RTT’. HMRC will email it to you up to 10 days after you submit your report.

After you receive your report reference number, use the ‘real time’ Capital Gains Tax service to change your report.

Report in a Self Assessment tax return

You can file a Self Assessment tax return to report your gains in the tax year after you disposed of assets.

If any of your gains are from UK property sold after 6 April 2020, you should have reported them within 30 days of the sale. You must still include these gains in your Self Assessment tax return, if you send one.

If you do not usually send a tax return, register for Self Assessment after the tax year you disposed of your chargeable assets.

If you’re already registered but have not received a letter reminding you to fill in a return, contact HMRC by 5 October.

You must send your return by 31 January (31 October if you send paper forms).

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

After you’ve sent your tax return

HMRC will tell you how much you owe. The Capital Gains Tax rate you pay depends on your Income Tax rate.

You’ll need to pay your tax bill by the deadline.

You’ll have to pay a penalty if you send your tax return late, miss the payment deadline or send an inaccurate return.