To register as a sole trader in the UK, you must register for Self Assessment with HMRC by 5 October in the tax year after you started trading. If you started in 2024/25, you must register by 5 October 2025. Registration is free and can be done online in around 20 minutes.

Quick summary

Register by 5 October following your first year of trading. Go to GOV.UK and register for Self Assessment. HMRC will send your Unique Taxpayer Reference (UTR) by post within 10 days. You will then be able to file your first tax return.

Who needs to register as a sole trader?

You must register as a sole trader and complete a Self Assessment tax return if any of the following apply to you:

  • You earned more than £1,000 from self-employment in the tax year (the trading allowance threshold)
  • You want to pay voluntary National Insurance contributions to protect your State Pension entitlement
  • You received a letter from HMRC asking you to register
  • You claimed Child Benefit and your or your partner's income exceeded £50,000 (the High Income Child Benefit Charge)

Even if your self-employment income is below £1,000, you may still choose to register to keep your National Insurance record intact.

How to register: step by step

1
Create a Government Gateway account
Go to GOV.UK and create a Government Gateway account if you do not already have one. You will need your National Insurance number and a valid email address.
2
Register for Self Assessment
Use the HMRC online form to register for Self Assessment as a self-employed person. You will provide your personal details, business name (if different from your own name), and the date you started trading.
3
Receive your UTR by post
HMRC will send your Unique Taxpayer Reference (UTR) number by post, usually within 10 working days. This is a 10-digit number you will use on all correspondence with HMRC.
4
Activate your online account
Once you receive your UTR, you can activate your Self Assessment online account on GOV.UK. This lets you file returns and view your tax position.
5
Consider VAT registration
If your taxable turnover exceeds or is likely to exceed £90,000 in the next 12 months, you must also register for VAT. Below this threshold, VAT registration is optional but may be beneficial.

When is the registration deadline?

You must register by 5 October in the second tax year of trading. For example:

You started trading inRegistration deadline
Any time in 2023/24 (before 5 April 2024)5 October 2024
Any time in 2024/25 (before 5 April 2025)5 October 2025
Any time in 2025/26 (before 5 April 2026)5 October 2026
Late registration penalty

Missing the 5 October deadline can result in a penalty. HMRC can charge up to 30% of the unpaid tax if failure to notify is deliberate. Register as soon as you start trading to avoid this risk.

What information do you need to register?

  • Your full name and date of birth
  • Your National Insurance number
  • Your home address and phone number
  • Your email address
  • The name of your business (if you trade under a business name)
  • The date you started self-employment
  • The nature of your business (a brief description)

You do not need to register your business name with Companies House as a sole trader. Only limited companies have this requirement.

Can you use a business name as a sole trader?

Yes. As a sole trader, you can trade under any name as long as it does not imply you are a limited company (for example, by including "Ltd" or "Limited"). Your business name cannot be offensive or identical to a registered trademark.

If you do trade under a business name, you must still display your own name on official documents such as invoices, letters, and your website.

What happens after you register?

Once registered, you will need to:

  • Keep records of all your income and expenses throughout the year
  • File a Self Assessment tax return each year by 31 January (online) or 31 October (paper)
  • Pay Income Tax on your profits and Class 4 National Insurance
  • Consider whether you are eligible for the trading allowance or cash basis accounting

Sole trader vs limited company: which should you choose?

Most people starting out should begin as a sole trader. It is simpler, cheaper to run, and requires less administration. As your income grows, it may make financial sense to incorporate. See our full guide to sole trader vs limited company for a detailed comparison.

Disclaimer

This guide provides general information only. It does not constitute tax or legal advice. For your specific situation, consult a qualified accountant or tax adviser. You can find an accountant through our directory.