How to Find Your UTR Number: 3 Quick Methods

The Accounted Business Team·17 January 2026·7 min read

What Is a UTR Number?

UTR stands for Unique Taxpayer Reference. It is a 10-digit number that HMRC assigns to every person or business registered for Self Assessment or Corporation Tax. Think of it as your tax ID — it is how HMRC identifies you in their system.

Your UTR is not the same as your National Insurance number. They serve different purposes. Your NI number tracks your National Insurance contributions and benefit entitlements. Your UTR is purely for tax purposes — specifically for Self Assessment and company tax.

Every sole trader, freelancer, and limited company director who files a tax return needs a UTR. You will need it to:

File your Self Assessment tax return
Log in to your HMRC online account
Communicate with HMRC about your tax affairs
Provide to clients or agencies who need to verify your tax status (common in construction under CIS)

If you have misplaced yours, do not panic. Here are three ways to find it.

Method 1: Check Your SA250 Letter

When you first registered for Self Assessment, HMRC sent you a letter called the SA250. This letter confirms your registration and contains your UTR prominently displayed near the top.

The SA250 typically arrives within 10 working days of registering, though it can take longer during busy periods. If you registered years ago, you might need to dig through your files, but this is the most straightforward place to find it.

Where to Look

Check old paperwork files or folders where you keep tax documents
Search your filing cabinet or drawer where you store official letters
Look for a letter with the HMRC logo that mentions "Self Assessment" and "Unique Taxpayer Reference"

The UTR is always 10 digits long, with no letters. It might be displayed with spaces (like 12345 67890) or without (1234567890), but it is the same number either way.

If you use Accounted, Penny stores your UTR securely within your account so you never have to hunt for it again. Once you enter it during setup, it is always there when you need it.

Method 2: Find It in Your HMRC Online Account

If you have already set up a Government Gateway account (the login system for HMRC's online services), your UTR is displayed in your account.

Step-by-Step

Go to www.gov.uk and search for "HMRC sign in"
Sign in using your Government Gateway user ID and password
Navigate to your Self Assessment account
Your UTR will be displayed on your Self Assessment homepage, usually near the top of the page

If you cannot remember your Government Gateway login, you can recover it through the sign-in page. You will need the email address or phone number linked to your account.

Check Previous Tax Returns

If you have filed a tax return before — whether online or on paper — your UTR will appear on it. Previous online submissions can be viewed through your HMRC account. Paper copies, if you kept them, will show your UTR at the top of the form.

Check Previous HMRC Correspondence

HMRC includes your UTR on virtually all correspondence related to Self Assessment. This includes:

Tax calculation letters (SA302)
Statements of account
Payment reminders
Coding notices related to Self Assessment
Penalty notices

Have a look through any HMRC letters you have received in the past year or two. Your UTR will be printed on them, usually in the top right corner or in a reference box.

Method 3: Phone HMRC Directly

If you cannot find your UTR through the methods above, you can phone HMRC and ask them to confirm it or resend it by post.

HMRC Self Assessment Helpline

Phone number: 0300 200 3310
Opening hours: Monday to Friday, 8am to 6pm (hours can vary, check gov.uk for current times)
What you will need: Your full name, date of birth, National Insurance number, and current address

Be prepared for a wait. HMRC phone lines can be busy, particularly between October and January when everyone is thinking about their tax return. Calling early in the morning or mid-afternoon tends to be slightly less painful.

HMRC will verify your identity by asking security questions, then either confirm your UTR over the phone or arrange to send it to your registered address by post. For security reasons, they may only send it by post rather than reading it out — it depends on the situation.

How Long Does It Take to Get a UTR by Post?

If HMRC needs to post your UTR to you, expect it to take around 10 working days. During peak periods (October to January), it may take longer.

What If You Have Never Registered?

If you have never registered for Self Assessment, you will not have a UTR yet. You need to register first.

How to Register for Self Assessment

Sole traders and freelancers: Register online at gov.uk. Search for "register for Self Assessment" and follow the steps. You will need your National Insurance number and details about your self-employment.
Partners in a partnership: The nominated partner must register the partnership, and each individual partner must register separately.
Company directors: If your limited company is already registered for Corporation Tax, it will have a company UTR. You personally need to register for Self Assessment separately if you need to file a personal return (most directors do).

How Long Does Registration Take?

After registering online, HMRC will send your UTR by post. This usually takes around 10 working days but can take up to 21 days. You cannot file your Self Assessment return without it, so do not leave registration to the last minute.

If you are coming up to the 31 January deadline and still waiting for your UTR, HMRC may accept that the delay was outside your control — but you should still file as soon as you receive it. Waiting until December to register when you know you have been self-employed since April is not a reasonable excuse for late filing.

UTR vs Other Tax References

It is easy to confuse your UTR with other reference numbers. Here is a quick guide to which is which.

UTR (Unique Taxpayer Reference)

10 digits, numbers only
Used for Self Assessment and Corporation Tax
Stays the same for life (unless you set up a new company, which gets its own UTR)

National Insurance Number

Format: two letters, six numbers, one letter (e.g., AB 12 34 56 C)
Used for NI contributions, benefits, and PAYE
Not the same as your UTR

PAYE Reference

Format: three numbers, a forward slash, then letters and numbers (e.g., 123/AB456)
Used by employers for payroll
Only relevant if you employ people

VAT Registration Number

9 digits, sometimes prefixed with "GB"
Only applies if you are VAT registered
Completely separate from your UTR

Keep Your UTR Safe

Your UTR does not change. Once you have it, write it down somewhere secure and keep it accessible. You will need it every year when filing your return, and potentially at other times if HMRC writes to you or you need to speak to them.

Some practical tips for keeping it safe:

Store it digitally in a password manager or secure notes app
Keep your SA250 letter in a dedicated tax folder
Add it to your bookkeeping software so it is always to hand

If you use Accounted, your UTR is stored securely within your account from day one. Penny references it when preparing your return, so you never need to go hunting for it in a drawer full of old letters.

Do Not Let a Lost UTR Slow You Down

Finding your UTR is straightforward once you know where to look. Check your HMRC letters, log in to your online account, or call HMRC if all else fails. The important thing is not to let a missing reference number stop you from filing on time — late filing penalties start at £100 and only go up from there.

If you want to keep all your tax details organised in one place alongside your income, expenses, and tax calculations, give Accounted a try. Start your free trial today and get your Self Assessment sorted without the stress.

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