Register for Self Assessment

You must register for Self Assessment before you can file a tax return online. Registering tells HMRC you have income or gains to report.

Who needs to register

You need to register if, in the last tax year, any of these applied:

  • you were self-employed and earned more than £1,000
  • you got income from renting out property
  • you sold cryptoassets and made a gain above the annual exempt amount
  • you received staking, mining or airdrop rewards
  • you got untaxed income, for example from tips, commission or savings interest above your allowance

Check if you need to send a tax return if you are not sure.

If you have never sent a tax return

Tell HMRC you need to complete a tax return for the first time. You must do this by 5 October after the end of the tax year. If you miss it you may have to pay a penalty.

You’ll need:

HMRC will post you a Unique Taxpayer Reference (UTR). It usually arrives within 10 working days. Keep it safe — you need it to sign in.

If you have registered before

If you registered for Self Assessment in an earlier year but did not need to send a return, your account may be dormant. Check whether you need to reactivate it before you file.

Your tax return may be delayed if you file it without reactivating an existing account.

After you register

Cryptoassets

If you have made gains from cryptoassets, you may need to register even if you have no other income. Check your cryptoassets to find out.