Your Unique Taxpayer Reference Explained
A Unique Taxpayer Reference (UTR) is a 10-digit number issued by HMRC when you register for self-assessment. It is used to identify your tax records and is needed every time you file a return, make a payment, or correspond with HMRC about your self-assessment.
You will receive your UTR by post within 10 working days of registering for self-assessment (or up to 21 days if abroad). If you lose it, you can find it on previous tax returns, HMRC correspondence, or by logging into your HMRC personal tax account.
Contractors and freelancers are often asked for their UTR by agencies and clients, as it is needed for CIS verification in the construction industry. Keep your UTR accessible for annual filing.
How Utr Number Works in Practice
A Unique Taxpayer Reference (UTR) is a 10-digit number issued by HMRC to individuals and businesses registered for self-assessment. You receive a UTR when you register as self-employed, as a company director, or when you need to file a tax return for other reasons (rental income, untaxed investment income). The UTR is permanent and does not change. If you're self-employed, use our self-employed tax calculator to see your exact take home pay.
Practical Tips
Your UTR is separate from your National Insurance number. You need it to file self-assessment returns, set up online access to HMRC's self-assessment system, and it may be requested by clients or agencies as proof of your self-employed status. Keep your UTR safe — it is sensitive information. If you lose it, HMRC can confirm it by phone or letter (call 0300 200 3310). It typically takes 10-20 working days to receive a UTR after registering for self-assessment.
How to Find Your UTR Number
Lost your UTR? There are three ways to find it:
1. Check your SA250 letter — HMRC sent this when you first registered for Self Assessment. Your 10-digit UTR is printed at the top.
2. Log into HMRC online — Sign in to your personal tax account on gov.uk. Your UTR is displayed in the Self Assessment section.
3. Call HMRC — Phone the Self Assessment helpline on 0300 200 3310 (Monday to Friday, 8am to 6pm). You will need to verify your identity.
How to Apply for a UTR Number
If you have never had a UTR, here is how to get one step by step:
Step 1: Register for Self Assessment on gov.uk. Choose the correct category (self-employed, landlord, etc.).
Step 2: HMRC will send your UTR by post to your registered address. This usually takes 10 working days (up to 21 days if abroad).
Step 3: Once you have your UTR, set up your HMRC online account to file returns and make payments digitally.
Tip: Register as early as possible — you cannot file a tax return without a UTR, and late registration can lead to penalties.
When Do You Need a UTR Number?
You need a UTR if any of the following apply to you:
- Self-employed — sole traders and freelancers must register for Self Assessment. Use our self-employed tax calculator to estimate your bill.
- Landlord — if you earn rental income, you need to declare it via Self Assessment.
- Earning over £100,000 — high earners must file a return even if all income is taxed through PAYE.
- Side income — if you earn more than £1,000 from a side hustle, you may need to register. See our guide on side hustle tax.
- Company director — directors with income outside PAYE need a UTR.
Learn more about the filing process in our Self Assessment guide.
Related Topics
Companies have a separate UTR for corporation tax purposes. Partnerships also receive their own UTR, in addition to each partner having a personal UTR. See self-assessment explained.
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