by Asim Abbas
11 November 2026 
How to register for Self Assessment and get your UTR
How to register for Self Assessment and get your UTR
If you’ve started self-employment, receive rent or have other untaxed income, you need to register for Self Assessment before you can file a return.
- Register by 5 October after the tax year
- For 2025/26 income, that was 5 October 2026
- Your UTR arrives by post or in the HMRC app
- Self-employed people also register for Class 2 and 4 NI
Registration gives you a Unique Taxpayer Reference, your UTR, which you’ll use with HMRC for life.
This guide explains who needs to register, the 5 October deadline and how to get your UTR.
Who needs to register?
- Self-employed income over £1,000 (the trading allowance)
- Rental income over £1,000, or over £10,000 before expenses
- Partners in a partnership
- Untaxed income such as tips or commission
- Savings or investment income over £10,000
- Capital gains to report
- High Income Child Benefit Charge, unless paid through your tax code
- Foreign income
The registration deadline
You must register by 5 October following the end of the tax year in which you had the income. Registering late can lead to a failure to notify penalty if tax is unpaid on 31 January, so don’t leave it.
Self Assessment tax calculator
See what you’ll owe.
How to register
| Your situation | How to register |
|---|---|
| Self-employed | Online, which also registers you for National Insurance |
| Not self-employed, such as a landlord | Online, or form SA1 |
| Partner in a partnership | Online, or form SA401 |
| Nominated partner registering the partnership | Online, or form SA400 |
You’ll need your National Insurance number, contact details and the date you started the income. You’ll sign in with your Government Gateway credentials, or GOV.UK One Login as HMRC moves services across.
Getting your UTR
Your UTR is a 10-digit number. After you register, it’s sent by post, usually within 15 working days, or 21 if you’re abroad. You can also see it in the HMRC app and your personal tax account once your registration is processed.
Callum started dog walking in June 2026 and expects to earn £9,000 by April 2027. He doesn’t have to register until 5 October 2027, but registering now means he gets his UTR in good time, can make Making Tax Digital decisions early and won’t miss the 31 January 2028 filing deadline.
Fixed-fee accountancy support
Transparent monthly packages for sole traders, landlords and limited companies. Fixed fees agreed upfront, VAT included.
Get a fixed-fee quoteCall 0161 531 4179Activation codes
You may also receive an activation code to use the online Self Assessment service. It expires after 28 days, so use it as soon as it arrives.
Making Tax Digital
If your qualifying income from self-employment and property is over the MTD threshold, you’ll need compatible software and quarterly updates as well. The threshold is £50,000 from April 2026 and £30,000 from April 2027. See our MTD guide.
Stopping Self Assessment
If you stop the income, tell HMRC so you aren’t asked to file returns you don’t need, but file the return for the final year.
Register through HMRC’s Self Assessment registration page, read our tax return checklist, or let our Self Assessment team register you.
What should I do next?
Income over £1,000?
After the tax year.
Post or HMRC app.
Frequently Asked Questions
When is the deadline to register for Self Assessment?
5 October after the end of the tax year. For 2025/26 income, that was 5 October 2026.
How long does it take to get a UTR?
Usually up to 15 working days by post, or 21 if you’re abroad.
Can I find my UTR online?
Yes, in the HMRC app or your personal tax account once registered.
Do I need to register if I earn under £1,000?
Usually not for trading or property income covered by the £1,000 allowances.
What happens if I register late?
You may get a failure to notify penalty if tax is unpaid.
Need help with this? Wingate Accountants offers fixed-fee online accountancy support across the UK. Call 0161 531 4179 or request a quote at wingateaccountants.co.uk.
About the Author
Ali Imran
I’m Ali Imran, an accountant at Wingate Accountants. I help sole traders, landlords and directors get their returns filed early and accurately, without the last-minute panic.
