UK HMRC Forms · 2026/27
What is a UTR Number? UK 2026/27 Guide
What it is
The UTR is the unique identifier for your self-assessment tax record. Format: 10 digits (e.g. 1234567890). It's distinct from your NINO (which identifies you for NI/State Pension) — you need both if you're self-employed: NINO for NI contributions, UTR for income tax via self-assessment. Companies have their own separate Corporation Tax UTR for limited company tax filings.
Who needs this
Anyone required to file a UK self-assessment tax return needs a UTR: self-employed sole traders, freelancers, contractors, landlords with rental income, partners in a partnership, company directors who need to file self-assessment, and anyone with significant other untaxed income (large investment income, foreign income, etc.). Standard PAYE-only employees don't need a UTR unless they have other income above thresholds.
When you'll see it
After registering for self-assessment via gov.uk. UTRs typically arrive by post within 10 working days, sometimes longer in busy periods (especially Jan-Apr). The letter is from HMRC and clearly states 'Your Unique Taxpayer Reference is...'. If you've registered online but haven't received the UTR, you can usually find it via your government gateway account once it's been issued.
How to get it
Register for self-assessment at gov.uk/register-for-self-assessment. You need: NINO, address, contact details, and reason for registration (self-employed, landlord, etc.). After registration, HMRC posts your UTR. If you've registered before (e.g. for previous self-employment), you keep the same UTR — don't re-register, just reactivate the old one. Lost UTR: find it on previous tax returns, HMRC letters, or via personal tax account.
Common issues
Common UTR issues: (1) UTR not received within 4 weeks of registration (call HMRC self-assessment helpline 0300 200 3310), (2) lost UTR (find it on previous tax returns or HMRC letters; don't apply for a new one — you can't have two), (3) tried to file return without UTR (you can't — the system requires it), and (4) UTR doesn't match HMRC records (could be transposition error or wrong person — contact HMRC).
Recruiter pro tip
Once you have a UTR, your obligation to file annual self-assessment returns continues until HMRC formally cancels it — even if you stop being self-employed. If you've registered for self-assessment but don't think you need to file (e.g. side income dropped below £1,000 trading allowance), call HMRC to formally cancel. Otherwise £100 late-filing penalties accrue every year for missed returns even if you owe no tax.
Related HMRC forms
National Insurance Number (NINO)?
Your National Insurance Number (NINO) is your unique UK tax and social security identifier — a 9-character cod…
SA100 Self Assessment Form?
The SA100 is the main UK Self Assessment tax return form. It's the document that reports all your income, tax-…
CWF1 Form? (Self-Employed Registration)
Form CWF1 is the UK form for registering as self-employed with HMRC. It establishes your self-assessment recor…