What is a UTR (your company's tax reference)?

Updated 27 June 2026
The short answer

Your UTR is a 10-digit number HMRC uses to recognise your company for Corporation Tax, a bit like a tax membership number. HMRC posts it to your company's registered office shortly after the company is set up, usually within a couple of weeks. You need it to register for, sign in to and file your Corporation Tax. It is not the same as your Companies House number, and not the same as your own personal tax number.

So what is a UTR, in plain terms?

UTR stands for Unique Taxpayer Reference. It's a 10-digit number that belongs to your company and nobody else's. HMRC uses it to know which company is which when it comes to Corporation Tax, the tax a limited company pays on its profit.

Think of it as your company's tax membership number. Every time your company talks to HMRC about Corporation Tax, the UTR is how HMRC pulls up the right file.

Where does my UTR come from?

You don't apply for it. As soon as your company is set up at Companies House (the moment it's "incorporated"), HMRC creates a Corporation Tax record for it and gives it a UTR.

HMRC then posts the number to your company's registered office, the official address you gave Companies House. That letter usually arrives within a couple of weeks of the company being set up. So if you've just started a company, keep an eye on the post going to that address.

This is also why it's worth checking your registered office address is right and that you'll actually see the post sent there, because that's where this letter lands.

What do I need my UTR for?

You need it for the Corporation Tax side of running your company. In plain terms:

  • To register your company for Corporation Tax with HMRC.
  • To sign in to HMRC's Corporation Tax service (part of your online business tax account).
  • To file your Company Tax Return each year and pay the right amount.

Without the UTR, HMRC can't match what you send to your company, so it's one of the first things you'll be asked for.

Where do I find my UTR?

A few reliable places:

  • On letters from HMRC. The number is printed on HMRC post about your company, including the letter that tells you to send in your Company Tax Return.
  • In your business tax account. Once your company is signed up to HMRC's online Corporation Tax service, the UTR shows up there when you sign in.

If you've filed before, it'll be on your earlier paperwork too.

What if I never got it (or I've lost it)?

It happens, post goes missing, or you took over a company and never saw the original letter. You can ask HMRC to send it again online. HMRC will post a copy to the company's registered office (the address registered with Companies House).

If it's been more than about 15 days since your company was set up and nothing has arrived, that's the point to go and request it rather than keep waiting.

Is the UTR the same as my Companies House number?

No, and this is the mix-up that catches people out. Your company actually has two different reference numbers:

  • The company registration number (sometimes called the CRN) comes from Companies House when the company is set up. It's how Companies House identifies your company.
  • The UTR comes from HMRC and is how the tax office identifies your company.

They're issued by different offices for different jobs, so they're different numbers. There's also a personal UTR, the one an individual gets for their own self assessment tax. Your company's UTR is separate from that too. If you run your own company, you might end up with both, your personal one and your company's one, and they are not interchangeable.

A quick example

Say you set up Bluebird Bakery Ltd on 1 June.

  • Companies House gives it a company registration number straight away, used on the public register.
  • A couple of weeks later, a letter from HMRC lands at the bakery's registered office with its 10-digit UTR.
  • When it's time to file, that UTR is the number HMRC uses to find Bluebird Bakery's tax record and match the return to it.

Same company, two numbers, two different offices.

How SimpleReturns handles it

When you file with us, we ask for your company's UTR once during sign-up, then use it to file your Corporation Tax for you. If you're not sure which number is your UTR, we'll show you exactly where to look, and you only ever enter it the one time.


Common questions

How many digits is a UTR?

Ten. If the number you're looking at isn't 10 digits, it isn't your UTR.

How long after setting up my company do I get my UTR?

Usually within a couple of weeks. HMRC posts it to your registered office after the company is set up. If it hasn't arrived after about 15 days, you can request it.

Where is my UTR if I can't find the letter?

On other letters from HMRC, or in your business tax account once your company is signed up to the Corporation Tax service online. If you still can't find it, you can ask HMRC to send a copy.

Is my UTR the same as my company number from Companies House?

No. The Companies House number identifies your company on the public register; the UTR identifies it for tax at HMRC. Two different numbers from two different offices.

Is my company's UTR the same as my personal tax UTR?

No. A personal UTR is for your own self assessment. Your company's UTR belongs to the company. If you have both, keep them apart.

Do I need my UTR to file my Corporation Tax?

Yes. It's how HMRC matches your return to your company, so you'll need it to register, sign in and file.

Ready to file without the headache?

You don't need to understand any of the tax behind your UTR to file. Give us the number once, and we work out your figures, fill in your Company Tax Return, and show you everything before anything is sent, for £99, once, no subscription.

Start your return →

Or, if your company is more complex, like a group, an accountant may be the better fit, and that's an honest call to make.

General guidance, not advice. This guide explains how the rules generally work for small UK limited companies. It isn't tax advice for your specific situation, if you're unsure, check with us or an accountant.