Becoming self-employed in the UK is an exciting step towards independence and financial control. Whether you’re freelancing, running a side hustle, or starting a full-time business, there are important legal steps you must take before you can trade compliantly.
One of the most common questions we hear is:
How do I apply for a UTR number and register as self-employed in the UK?
In this guide, we explain exactly:
- What a UTR number is
- Why you need one
- How to register as self-employed with HMRC
- What to do once your UTR arrives
This guide is designed to help you get set up correctly without confusion or delays.
What Is a UTR Number?
A Unique Taxpayer Reference (UTR) is a 10-digit number issued by HM Revenue & Customs (HMRC). It is used to identify individuals and businesses for tax purposes.
If you’re self-employed, your UTR number is essential for:
- Filing Self Assessment tax returns
- Paying Income Tax and National Insurance
- Communicating with HMRC about your tax affairs
Think of your UTR as your personal tax ID. You’ll need it every year, so it’s important to keep it safe.
Why Do You Need a UTR Number?
When you start working for yourself, HMRC must be informed so they can track your income and tax obligations. Without a UTR number, you won’t be able to:
- File a Self Assessment tax return
- Pay Income Tax or National Insurance Contributions (NICs)
- Claim allowable business expenses or tax reliefs
- Access HMRC online services properly
In short, you cannot meet your legal tax obligations as a sole trader without a UTR number.
How to Apply for a UTR Number in the UK
You don’t apply for a UTR number separately. Instead, HMRC issues it automatically once you register for Self Assessment.
Step 1: Register as Self-Employed with HMRC
Before you receive a UTR number, you must first register as self-employed in the UK.
Most people do this as a sole trader, which is the simplest structure for freelancers and independent workers.
How to register:
- Go to the official HMRC website
- Search for “Register as self-employed”
- Complete the Self Assessment registration form
- Provide:
- Full name
- Address
- Date of birth
- National Insurance number
- Start date of self-employment
- Business name (if different from your own)
Once submitted, HMRC will process your registration.
Deadline:
You must register by 5 October following the end of the tax year in which you started trading.
Step 2: Receive Your UTR Number
After registering, HMRC will send your UTR number by post to your registered address.
- Typical processing time: 7–10 working days
- During busy periods, it may take longer
If you don’t receive your UTR within two weeks, you should contact HMRC to request it.
Once received, keep your UTR number secure — you’ll need it every year.
What If You’re Setting Up a Limited Company?
If you plan to operate as a limited company, the process is slightly different:
- You register the company with Companies House
- HMRC then issues:
- A company UTR
- A personal UTR (if you’re required to file Self Assessment as a director)
Limited companies have different tax responsibilities, so professional guidance is often recommended at this stage.
Common Mistakes to Avoid When Applying for a UTR Number
Although the process is straightforward, mistakes can cause delays or penalties. Watch out for the following:
Registering too late
Failing to register on time can result in HMRC penalties.
Losing your UTR number
You’ll need it every year — store it securely.
Entering incorrect details
Errors in names, addresses, or start dates can delay registration.
Not updating HMRC
If your circumstances change (e.g. employment status or income), HMRC must be informed.
What to Do After Receiving Your UTR Number
Once you have your UTR number, you can:
File your Self Assessment tax return- Pay Income Tax and National Insurance
- Claim allowable business expenses
- Access your HMRC online tax account
Your first tax return is usually due by 31 January following the end of the tax year.
How Long Does It Take to Get a UTR Number?
In most cases:
- 7–10 working days after registering
- Longer during peak periods (December–January)
If your UTR hasn’t arrived within the expected timeframe, contact HMRC to follow up.
Do You Need a UTR Number for Every Type of Self-Employment?
Yes — if you are:
- A sole trader
- A freelancer
- Earning income not taxed through PAYE
- Required to submit Self Assessment
Employees paid entirely through PAYE generally do not need a UTR unless they have additional income.
Conclusion
Understanding how to apply for a UTR number and register as self-employed in the UK is a crucial first step in your self-employment journey. While the process is manageable, it must be done correctly and on time to avoid penalties.
