How to Register as Self-Employed UK: Step-by-Step Guide for 2026
Registration Deadline
You must register as self-employed with HMRC by 5 October following the end of the tax year in which you started trading.
💡 Quick Tip
Thistle reminds you of all HMRC deadlines automatically—never miss registration, tax returns, or payment dates.
How to Register Online
- Go to GOV.UK: Visit gov.uk/register-for-self-assessment
- Create a Government Gateway account (if you don't have one)
- Provide your details: Name, address, National Insurance number, business start date
- Describe your business: Trade type and nature of work
- Submit: Registration is instant
- Receive UTR: Your Unique Taxpayer Reference arrives by post in 10 days
What You Need
- National Insurance number
- Business start date
- Business address (can be your home)
- Business description
- Contact phone number
Start Tracking from Day One
Once registered, start tracking income and expenses immediately with Thistle. Be ready for your first tax return.
Start Free Trial →Frequently Asked Questions
When do I need to register as self-employed?
You must register by 5 October following the end of the tax year in which you started trading. For example, if you started in July 2025, register by 5 October 2026.
How long does registration take?
Online registration is instant. You'll receive your Unique Taxpayer Reference (UTR) within 10 working days by post.
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