UTR number (Unique Taxpayer Reference)
What it is
A 10-digit number HMRC assigns to every UK company and self-employed individual when they register for tax. Companies receive a Corporation Tax UTR; individuals receive a personal UTR for Self Assessment. The two are different numbers.
Why it matters
You need your company UTR to file Corporation Tax returns, pay tax and communicate with HMRC. HMRC sends it by post to your registered office — another reason a reliable registered-office address matters.
Common mistake
Confusing the company UTR (10 digits, from HMRC) with the company registration number CRN (8 digits, from Companies House). Banks and accountants need both and they are not interchangeable.
Official source
GOV.UK — Find your UTR number ↗Disclaimer
General educational guidance only — not legal, tax, accounting, immigration, investment or financial advice. We don't guarantee the information is complete, current or suitable for your situation. Always check official sources (GOV.UK, Companies House, HMRC, the relevant professional body) and speak to a qualified professional before acting. Last reviewed: June 2026.