Registering as self-employed means registering for Self Assessment as someone who works for themselves. It is one online form on GOV.UK. There is no fee, and once it is done HMRC sets you up to file a tax return each year.
Before you start
Have these ready:
- Your National Insurance number.
- Your address and date of birth.
- The date you started trading. Use the date of your first sale or first invoice, or the day you genuinely started running as a business, whichever is clearest.
- A short description of the work, for example "mobile hairdresser" or "freelance copywriter".
You do not need business accounts, a business name, or any income figures yet. This step is only telling HMRC you exist.
The steps
- Check you actually need to register. If your gross self-employed income for the tax year was £1,000 or less and none of the other triggers apply, you can stop here.
- Go to GOV.UK and search "Register for Self Assessment". Choose the self-employed option.
- Sign in with your Government Gateway user ID, or create one. Creating one takes a couple of minutes and needs an email address and a phone.
- Fill in the form. Personal details, the start date, the type of work. If you have never had a Unique Taxpayer Reference before, this is the first-time route and it also registers you for Class 2 National Insurance at the same time.
- Submit. You get an on-screen confirmation. Save or screenshot it.
If you have registered for Self Assessment before
If you have ever had a UTR, for example from a previous spell of self-employment, a rental property, or a year you were pushed into Self Assessment for another reason, do not create a second one. Use the route for people who have sent a return before, which reactivates your existing record. Registering twice creates duplicate records that are a nuisance to untangle later.
What happens after you submit
HMRC posts your Unique Taxpayer Reference, a ten-digit number, usually within about ten working days. From abroad it can take longer. You cannot file a return without it, so treat the wait as part of the timeline.
You may also receive a separate letter with an activation code for your online Self Assessment account. If you get one, sign in and enter it within the time stated on the letter, or you have to request a new one.
After that you are in the system. HMRC will tell you which tax year's return they expect and when. For most new registrations the first return is due by the 31 January after the tax year in which you started.
The mistake that costs people
Leaving registration until you sit down to do the tax return. The return needs the UTR, the UTR comes by post, and the post takes time. If you register in mid-January hoping to file by the 31st, you will miss the deadline waiting for the number to turn up. Register as soon as you know you are over £1,000, even if the return itself is months away. If you are already late, see registering late.