What a UTR is
Your UTR is a reference number, a bit like an account number. HMRC uses it to match your tax return, payments and letters to the right record. It's 10 digits long and is sometimes called a tax reference or Self Assessment reference.
It's issued once and doesn't change. If you stop filing for a few years and then need to file again, you use the same UTR.
Personal UTR vs company UTR
| Personal UTR | Company UTR | |
|---|---|---|
| Who it belongs to | You as an individual | Your limited company |
| When you get it | After registering for Self Assessment | After incorporating at Companies House |
| Used for | Self Assessment tax returns (SA100) | Corporation Tax returns (CT600) |
| Where to find it | HMRC app, Personal Tax Account, HMRC letters | Business tax account, letters to the registered office |
If you're a company director you might have both: the company's UTR for Corporation Tax, and your own UTR if you need to file a personal return — for example for dividends above the allowance. See our company directors page.
What you use your UTR for
- Filing your Self Assessment tax return.
- Paying your tax bill — the payment reference is your UTR followed by K. See how to pay.
- Talking to HMRC about your account.
- Registering for the Construction Industry Scheme as a subcontractor — see CIS tax refunds.
- Giving it to an accountant or tax software so they can prepare your return.
Is it safe to share?
Your UTR isn't a password and can't be used on its own to access your account, but it is personal tax information. Share it only with HMRC, your accountant, legitimate tax software and, if you're a subcontractor, the contractors who need it to verify you under CIS.
Watch out for scams
HMRC won't text or email you asking for your UTR alongside bank details or offering a refund. If in doubt, sign in to your account directly rather than following a link.Next steps
Need to find yours? Read how to find your UTR number. Don't have one yet? See how to get a UTR number.
UTR vs other HMRC numbers
HMRC uses several references, and it's easy to mix them up:
| Number | What it looks like | What it's for |
|---|---|---|
| UTR | 10 digits | Self Assessment (or Corporation Tax for companies) |
| National Insurance number | 2 letters, 6 numbers, 1 letter | Employment, NI contributions and benefits |
| Tax code | Numbers and letters, e.g. 1257L | How much tax-free pay your employer gives you |
| Employer PAYE reference | 3 digits, a slash, then letters and numbers | Identifies your employer — shown on your P60 |
| VAT number | 9 digits, often with GB | VAT-registered businesses |
| Government Gateway user ID | 12 digits | Signing in to HMRC online services |
When a form asks for your tax reference in a Self Assessment context, it almost always means your UTR. Your P60 shows your employer's PAYE reference, not your UTR.