How to Report Capital Gains Tax

How you report Capital Gains Tax to HMRC depends on what type of asset you've sold. If you've sold UK residential property, you must use the special Capital Gains Tax property reporting service and report within 60 days. For other assets like shares or business assets, you can...

Introduction

Reporting UK residential property sales

If you've sold UK residential property, you must report and pay any Capital Gains Tax due within 60 days of completing the sale. This deadline applies even if you jointly own the property—you must report your own share of any gain or loss.

You may have to pay interest and a penalty if you do not report and pay on time.

Using the Capital Gains Tax on UK property account

You report property sales through a Capital Gains Tax on UK property account. You can sign in to an existing account or create one when you first use the service.

Before you start, you'll need:

The address and postcode of the property
The date you got the property
The date you exchanged contracts when selling
The completion date (when you stopped being the property's owner)
The value of the property when you got it and when you sold it
Costs of buying, selling or making improvements to the property
Details of any tax reliefs, allowances or exemptions you're entitled to claim
Property type, if you're not a UK resident

When you don't need to report property sales online

If you're a UK resident, you do not need to report your gains online if your total gains are less than the tax-free allowance (£3,000 for the 2025/26 tax year).

However, if you're not a UK resident, you must report all sales of UK property or land by the deadline, even if you have no tax to pay.

If you cannot use the online service

If you cannot report online, you'll need to complete an online form, print it and send it to HMRC. HMRC will then send you a 14-character Capital Gains payment reference number starting with 'X'. You'll need this reference number to pay what you owe by the deadline.

Reporting for someone else

You can use your own Capital Gains Tax on UK property account to report for someone else. You'll need proof you're allowed to report on their behalf, such as a lasting power of attorney. If the person has died, you'll need their date of death.

If you're reporting a gain on behalf of an estate as a personal representative (executor or administrator), you cannot pay using your account. HMRC will tell you how to pay after you report the gain.

Self Assessment and property sales

If you're already registered for Self Assessment, you'll also need to include details of the property sale in your Self Assessment tax return, in addition to reporting through the Capital Gains Tax on UK property account.

Reporting other capital gains

If your capital gain is not from UK residential property—for example, from selling shares, business assets or personal possessions—you can report your gain in one of two ways:

Through Self Assessment

You can report your gains in a Self Assessment tax return in the tax year after you sold or disposed of an asset. After you've submitted a return, HMRC will tell you how much you owe, how to pay and when to pay.

Using the 'real time' Capital Gains Tax service

You can use this service to report gains on assets you sold during the tax years 2025 to 2026 or 2026 to 2027.

You must be a UK resident to use this service. You cannot use it to report on behalf of someone else, for example a client, trust or estate.

You cannot use the service to report:

Gains on UK residential property
Foreign tax credit relief for overseas property
Chargeable event gains for life insurance

When you must report even with no tax to pay

If you're registered for Self Assessment, you need to report your gains in your tax return if the total amount you sold the assets for was more than £50,000 for the tax year 2023 to 2024 onwards. This applies even if your total taxable gains are under your £3,000 Capital Gains Tax allowance.

For tax years before 2023 to 2024, the reporting threshold was 4 times your allowance.

Information you need before reporting

Before you can report any gains, you'll need:

Details of how much you bought and sold the asset for
The dates when you took ownership and disposed of the asset
Any other relevant details, such as the costs of buying, selling or making improvements to the asset and any tax reliefs you're entitled to
Calculations for each capital gain or loss you report

Viewing and changing previous returns

You can use your Capital Gains Tax on UK property account to view and change your own previous returns.

If you made a return for someone else and need to change it, you'll need to complete an online form, print it and send it to HMRC.

You cannot change a return:

For the 2023 to 2024 tax year or earlier
If you have already sent a Self Assessment return for the same tax year as the Capital Gains Tax on UK property return

Reporting for trusts

If you're reporting on behalf of a trust, you'll need a Unique Taxpayer Reference (UTR) or Unique Reference Number (URN). If you do not have one, you must register the trust with HMRC, even if the trust is usually exempt.

If you're a non-resident trust, you must submit a report by the deadline even if there is no Capital Gains Tax to pay.

Corporate trustees must report their Capital Gains Tax on UK property by post.

Sources

This article provides general guidance based on current HMRC rules. For advice specific to your situation, speak to your accountant.