It’s a question often asked of accountants. I’ve started working for myself, how do I tell HMRC I need to complete a tax return?
Working for yourself means you are classed as a sole trader. This makes you self employed even if you haven’t told HMRC.
How to register with HMRC if you are self employed
If you have sent a return online before
Use HMRC’s Re-register online form (CWF1). You will need your 10 digit Unique Taxpayer Reference Number (UTR)
If you haven't sent a return online before
Use HMRC Register online service. When you register HMRC will send you a letter with your 10 digit Unique Taxpayer Reference and set up your account for the Self Assessment online service.
If you already have a UTR , for example because you registered by phone or you sent paper tax returns in the past, then you need to create an account for the online service instead.
An alternative method of registering is to fill this form on-screen then print off and post to HMRC. You’ll need to have all your information ready as you cannot save a partly completed form.
What is the deadline for telling HMRC?
You must tell HMRC by 5 October following the end of the first tax year in which your business traded.
For someone becoming self employed between 6 April 2018 and 5 April 2019 they need to register with HMRC by 5 October 2019.
If you don’t do this then you could be fined.
What happens after I register?
HMRC will write to you within 10 working days (21 days if you’re abroad) with an activation code for your online account. You need this code the first time you sign in to your online account.