Your Corporation Tax reference number, formally called a Unique Taxpayer Reference (UTR), is a ten-digit number HMRC assigns to every limited company shortly after it registers with Companies House. To find it, check any letter HMRC has sent about your company’s tax, sign in to your Business Tax Account, or look at a previously filed Company Tax Return. If none of those work, you can request a replacement through GOV.UK and HMRC will post it to your registered office within about 15 working days.1GOV.UK. Find Your UTR Number
Check HMRC Letters First
Almost every piece of Corporation Tax correspondence HMRC sends carries the UTR at the top of the page. One detail catches out a lot of directors: HMRC letters often print a 13-digit reference, and your UTR is only the last ten digits of that string.2HM Revenue & Customs. Completing Your Company Tax Return Enter all thirteen into filing software and it will reject the number.
The three letters worth digging out:
- The CT41G, sent automatically after incorporation. It lists the UTR, your first accounting period dates, and your initial filing deadline. HMRC asks you to allow at least 15 working days from incorporation before treating it as missing.3GOV.UK. Set Up a Private Limited Company – Add Corporation Tax Services to Your Business Tax Account
- The CT603, the annual notice to file. HMRC issues one for each accounting period, and the UTR sits on the front of it.
- Payment reminders, assessments, and general correspondence, all of which print the reference near the top.1GOV.UK. Find Your UTR Number
Sign In to Your Business Tax Account
If your company is already enrolled for HMRC online services, the UTR is visible inside the Business Tax Account. Log in through the Government Gateway, open the Business Tax Summary, and select Corporation Tax. The reference appears alongside the current balance and upcoming deadlines.
The catch: enrolling for Corporation Tax online requires the UTR in the first place, so this route only helps if you or a previous director already completed the setup.3GOV.UK. Set Up a Private Limited Company – Add Corporation Tax Services to Your Business Tax Account If nobody ever did, move on to the replacement request.
Look at a Previous Company Tax Return
Every CT600 filed with HMRC carries the UTR in the tax reference box on the front page.2HM Revenue & Customs. Completing Your Company Tax Return If your company has filed even once, pulling up the most recent return is one of the most reliable ways to recover the number. Commercial filing software usually stores it in the company profile as well, so if you know which product was used, that saves opening the PDF.
Ask Your Accountant
The route most directors skip, and often the fastest. Any accountant or tax agent who acts for your company will have the UTR on file, and an authorised agent can also see it directly through HMRC’s agent portal. A quick email or call usually confirms the number the same day, well ahead of any postal replacement.
Request a Replacement from HMRC
When nothing else turns it up, GOV.UK has an online tool for exactly this. You give your company name and registration number, and HMRC posts the UTR to the address registered at Companies House.1GOV.UK. Find Your UTR Number For security, HMRC will not read the number out on the phone or send it by email, and the letter goes only to the registered office. Check that address is current on Companies House before you submit the request.
Delivery takes around 15 working days.3GOV.UK. Set Up a Private Limited Company – Add Corporation Tax Services to Your Business Tax Account If a filing deadline is closer than that, the Corporation Tax helpline on 0300 200 3410 (Monday to Friday, 8am to 6pm) may be able to help with next steps, though staff still will not disclose the UTR itself over the line.4GOV.UK. Corporation Tax – General Enquiries Late filing triggers an automatic £100 penalty on day one, a further £100 at three months, and a 10% surcharge on unpaid tax at six months, so acting early on a missing UTR matters.5GOV.UK. Company Tax Returns – Penalties for Late Filing
Where You Will Not Find It
Companies House holds your company registration number, registered address, officer details, and filing history, but not your Corporation Tax UTR. The two numbers do different jobs: the registration number identifies your company at Companies House, and the UTR identifies it with HMRC. Searching the public register will not surface the UTR, though you will need the registration number when you request a replacement.
Your PAYE reference and VAT number are also separate identifiers, issued for payroll and VAT respectively. Neither can stand in for the UTR on a Company Tax Return, and neither will appear on Corporation Tax correspondence in place of it.