What Is a UTR Number?
UTR stands for Unique Taxpayer Reference. It's a 10-digit number issued by HMRC to identify you — or your business — for tax purposes. You'll sometimes see it called a Unique Tax Reference or Unique Taxpayer Reference number; it's all the same thing.
HMRC assigns a UTR when you register for Self Assessment or Corporation Tax. Once issued, it stays with you permanently. It's how HMRC links your returns, payments, and correspondence to your tax record.
What a UTR Looks Like
A UTR is always 10 digits — for example, 1234567890. On official HMRC letters it may appear with a trailing letter when used as a payment reference (e.g., 1234567890K), but the core number is always numeric and always 10 digits. If someone sends you a UTR that doesn't match this format, treat it with scepticism.
Personal UTR vs Company UTR
These are two distinct numbers used in different contexts:
| Type | Issued to | Used for |
|---|---|---|
| Personal UTR | Individual (sole trader, director, partner) | Self Assessment tax returns |
| Corporation Tax UTR | Limited company | Company tax returns, CT payments |
A company director often needs both — a personal UTR for their individual Self Assessment and a separate company UTR for Corporation Tax. These are not interchangeable.
UTR vs Other UK Tax Numbers
It's easy to confuse a UTR with other identifiers. Here's a quick reference:
| Number | What it is | Issued by |
|---|---|---|
| UTR | Tax reference for HMRC filings | HMRC |
| National Insurance number | Personal NI record (e.g., AB123456C) | HMRC / DWP |
| Tax code | Determines PAYE deductions (e.g., 1257L) | HMRC |
| Company Registration Number (CRN) | Identifies a company at Companies House | Companies House |
| VAT number | VAT registration reference | HMRC |
| PAYE reference | Employer reference for payroll | HMRC |
Your UTR is not a login credential and should never be used as one.
Who Needs a UTR?
Not everyone requires one. If all your income is taxed at source through PAYE and you have no other tax obligations, you probably don't need to register. But you will need a UTR if you fall into any of the following categories.
Sole traders and freelancers must register for Self Assessment once self-employment income begins — even before you've earned anything significant. Landlords with rental income, those with investment income above certain thresholds, and higher earners with untaxed income also need to register.
CIS subcontractors and contractors need a UTR for registration and verification within the Construction Industry Scheme. Without one, contractors must deduct tax at the higher 30% rate rather than the standard 20%.
Partnerships have a UTR of their own, and each individual partner also needs a personal UTR. Both are used when filing partnership and individual returns.
Limited companies receive a Corporation Tax UTR from HMRC shortly after incorporation — typically within a few weeks of the company being registered at Companies House. Directors who draw salary or dividends above the relevant thresholds will also need personal UTRs.
Trusts, estates, and non-UK residents with UK income may also need to register, depending on the nature and scale of their tax obligations.
⚠ Important: The deadline to register for Self Assessment is 5 October following the end of the tax year in which you became liable. Missing this date can result in penalties, even if you file and pay on time later.
How to Apply for a UTR Number (It's Free)
Applying for a UTR costs nothing. HMRC issues it directly — no intermediaries required. If you come across a website charging a fee to "apply for your UTR," close the tab.
Online (the most common route)
Most people register through GOV.UK via the Government Gateway. The exact journey depends on your circumstances:
- Sole traders and individuals complete the SA1 form or use the dedicated self-employed registration path at
gov.uk/register-for-self-assessment. You'll need a Government Gateway account; if you don't have one, you create it during the process. - Partnerships register the partnership itself to obtain a partnership UTR (using form SA400), then each partner registers individually (SA401 for new partners without an existing UTR).
- Limited companies don't apply directly — HMRC sends a Corporation Tax UTR automatically after incorporation. You do need to confirm your company's details and set up a business tax account to manage it online.
By Phone or Post
Calling HMRC is worth considering if you're dealing with an unusual situation — for instance, if you've moved abroad and can't verify your identity online, or if there's an error in your existing record. Have your National Insurance number, address history, and business details to hand before you call.
Postal registration remains an option using forms SA1, SA400, or SA401 as appropriate. Allow additional time, as postal processing is slower than online.
Information You'll Need
Gathering this in advance saves frustration.
For individuals and sole traders: full name, date of birth, National Insurance number, contact details, address history (two years is usually sufficient), business start date, and a brief description of your business activity.
For partnerships: the partnership name, address, nature of business, start date, and the names, addresses, and NI numbers of all partners.
For limited companies: company name, CRN, incorporation date, registered office address, principal trading address, accounting period start date, and contact details for a director.
How Long Does It Take?
For UK residents registering online, HMRC typically issues a UTR within 10 working days. The letter is sent to your registered address — so make sure it's correct before you submit. If you're overseas, allow up to 21 days.
After receiving your UTR, you'll still need to activate your Self Assessment online account using a separate activation code, which HMRC posts to you. This can add another week or so to the process, so don't leave registration until the last minute if you have a filing deadline approaching.
If your UTR hasn't arrived after the expected window, check that your address is correctly registered with HMRC, then call the Self Assessment helpline to request a reissue.
How to Find or Recover Your UTR
Your UTR appears on several HMRC documents, including:
- Your Self Assessment welcome letter
- SA100 and other tax return forms
- Notices to file and payment reminders
- Your HMRC online account (Personal Tax Account or Business Tax Account)
If you've lost it, the quickest route is usually logging into your Government Gateway account and checking your personal tax record. Alternatively, you can call HMRC and go through identity verification to have it confirmed or re-sent by post.
For a lost company UTR, log into your business tax account or call the Corporation Tax helpline. If the company is newly incorporated and the UTR letter hasn't arrived, check that Companies House has the correct registered office address — HMRC sends the letter there automatically.
Using Your UTR Correctly
When You'll Be Asked for It
Your UTR comes up more often than you might expect: when filing Self Assessment returns, making tax payments to HMRC, registering under CIS, sharing details with your accountant, and occasionally during KYC checks for banking or finance applications.
Paying HMRC with the Right Reference
When making Self Assessment payments, use your 10-digit UTR followed by the letter K as the payment reference (e.g., 1234567890K). For Corporation Tax, the reference is your UTR plus the accounting period. Using the wrong reference means HMRC can't match your payment to your account — which causes unnecessary hassle.
💡 Tip: Always confirm the exact payment reference on your HMRC account or in your latest HMRC notice before making a payment. A misallocated payment can trigger a late payment warning even if the money has left your account.
Sharing Your UTR Securely
Your UTR isn't a secret in the same way a password is, but you should still be careful. Share it only with HMRC, your accountant, or authorised parties who have a legitimate reason to request it — such as a contractor verifying you under CIS. Be alert to phishing attempts; HMRC will never ask for your UTR via text message or unsolicited email.
Deadlines, Penalties, and Compliance
| Deadline | What it covers |
|---|---|
| 5 October | Register for Self Assessment (after end of tax year you became liable) |
| 31 January | Online Self Assessment filing and payment of tax due |
| 31 July | Second payment on account (if applicable) |
| 9 months after year-end | Company accounts due at Companies House |
| 12 months after year-end | Corporation Tax return (CT600) filing deadline |
Late registration carries a penalty, as does late filing and late payment. If you have a genuine reason for missing a deadline — illness, bereavement, technical issues with HMRC systems — you can appeal using a "reasonable excuse" claim. HMRC does consider these on their merits, but they're not guaranteed.
Common Mistakes and Troubleshooting
Duplicate UTRs can arise if you've registered more than once or if HMRC's records have a legacy entry from a previous period of self-employment. If you suspect you have two UTRs, contact HMRC to consolidate them — filing on the wrong one creates a tangle that takes time to unpick.
Format validation: there's no public UTR checker. If you need to verify that a UTR you've received is plausible, check that it's exactly 10 digits and numeric. HMRC validates UTRs internally; you cannot look up whether one belongs to a specific person or company.
Avoiding paid intermediaries: a search for "apply for UTR number" will surface numerous third-party sites that charge anywhere from £20 to £100 to submit a registration on your behalf. This is not necessary. The GOV.UK registration is straightforward and entirely free.
FAQs
Can I get a UTR without a National Insurance number? In most cases, no — your NI number is used to verify your identity during registration. Non-UK nationals who don't yet have an NI number may need to apply for one first or contact HMRC directly to discuss alternative identification routes.
Do I need a UTR to claim a tax refund? Not always. Simple refunds can sometimes be processed without Self Assessment. However, if your refund involves income from self-employment or other untaxed sources, you'll likely need to file a return — and therefore need a UTR.
Can I run multiple businesses under one UTR? Yes. Your personal UTR covers all your self-employment income, regardless of how many sole trader activities you run. Each is declared on the same Self Assessment return. Limited companies, however, each have their own separate Corporation Tax UTR.
What if I set up as a sole trader months ago and forgot to register? Register as soon as possible. HMRC expects you to register by 5 October after the end of the tax year in which you started trading. If you've missed that, registering late is still far better than not registering at all — penalties are lower when you come forward voluntarily.
How do I get my UTR if I've moved abroad? You can still register online if you have a Government Gateway account and a UK address on record. If not, contact HMRC's Self Assessment helpline for guidance on registering from overseas. Allow extra time for any correspondence to reach you.
Glossary
Self Assessment – HMRC's system for reporting and paying tax on income that hasn't been taxed at source.
Government Gateway – HMRC's online portal for managing taxes, submitting returns, and accessing your tax account.
Corporation Tax – Tax paid by limited companies on their profits.
CRN (Company Registration Number) – A unique number assigned to a company by Companies House, distinct from its UTR.
PAYE reference – An employer's reference used for payroll reporting; not the same as a UTR.
Accounting period – The period covered by a company's tax return, usually 12 months.