What Is a UTR Number? Tax Reference Guide (2026)
A UK tax reference number most commonly refers to your Unique Taxpayer Reference (UTR) — a 10-digit number HMRC issues to identify you or your company for tax purposes. It’s essential for filing Self Assessment, paying Corporation Tax, and any dealings with HMRC. This guide from Filing Accounts UK explains what it looks like, who needs one, and how to find it.
At Filing Accounts, we help clients locate and use their UTR correctly. Official guidance is available at GOV.UK: Find your UTR number.
What Does a UTR Look Like?
A UTR is a 10-digit number, often shown with a space in the middle for readability (e.g. 12345 67890). It may appear as “tax reference” on HMRC letters and documents. Your UTR stays the same for life once issued — it doesn’t change if you change jobs, address, or business structure (a new company, however, gets its own separate UTR).
Who Needs a UTR?
You’ll be issued a UTR if you:
- Register for Self Assessment — self-employed, freelancers, landlords, or anyone with untaxed income
- Set up a limited company (the company itself gets its own UTR)
- Become a partner in a business partnership
Most employees who only receive PAYE income don’t need a UTR, unless they have additional income requiring Self Assessment.
UTR vs Other UK Tax References
| Reference | Who Needs It | Format | Main Use |
|---|---|---|---|
| UTR | Self-employed, directors, landlords | 10 digits | Self Assessment & Corporation Tax |
| PAYE Employer Reference | Employers with staff | e.g. 123/AB45678 | Payroll & RTI submissions |
| VAT Registration Number | VAT-registered businesses | GB + 9 digits | VAT returns |
| National Insurance Number | All adults working in the UK | AA 12 34 56 B | National Insurance contributions |
| Company Registration Number (CRN) | All limited companies | 8 digits or letters | Companies House filings |
Your UTR is different from your National Insurance number and your PAYE tax code — these are commonly confused but serve entirely separate purposes.
How to Find Your UTR
- HMRC Personal Tax Account — the fastest route: sign in via Government Gateway and check Self Assessment
- Previous tax documents — your SA302 tax calculation, previous Self Assessment returns, your SA250 welcome letter, or any HMRC payment reminders
- Company documents (for limited companies) — your CT41G letter, sent shortly after incorporation, or previous Corporation Tax returns
- Contact HMRC directly — via the Self Assessment helpline, with your National Insurance number ready
How to Get a UTR If You Don’t Have One
- Self-employed individuals: register for Self Assessment online via GOV.UK — your UTR typically arrives by post within 10–15 working days.
- Limited companies: HMRC automatically issues a UTR via a CT41G-style letter shortly after incorporation. If it’s been lost, you can request a copy directly from HMRC.
Why Your UTR Matters
- Required to file Self Assessment returns, online or on paper
- Needed to make tax payments correctly, including Payments on Account
- Used by HMRC to link all your tax records together
- Essential for claiming tax refunds
Using the wrong reference on a payment can cause delays, misallocated payments, or unnecessary penalties — see our guide on how to pay HMRC correctly.
Frequently Asked Questions
Is a UTR the same as a tax reference number?
Yes — UTR is the most common type of tax reference number, used for Self Assessment and Corporation Tax.
Can I have more than one UTR?
Usually just one per person or company, though rare circumstances (such as bankruptcy) can result in more than one.
What if I’ve lost my UTR?
Check your HMRC Personal Tax Account first, or contact HMRC directly if you can’t locate it another way.
Do I need a UTR if I’m only a PAYE employee?
No, unless you have additional income that requires you to file Self Assessment.
Need Help With Your UTR? Talk to Filing Accounts UK
At Filing Accounts, we help clients locate their UTR, register for Self Assessment, and use the right reference across every HMRC payment.
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