What’s New with Self Assessment Registration
HM Revenue & Customs introduced an Improved Self Assessment registration service on 9 September 2026.(gov.uk) Key changes include:
- Faster registration for beginners: Forms are now pre-populated, digital entry includes save / return functionality.(gov.uk)
- Digital & speedier Unique Taxpayer Reference (UTR): If registering new, you’ll receive your UTR via your online Personal Tax Account within 72 hours, instead of up to 15 days via post.(gov.uk)
- Streamlined communication and support: Signposting to help within the form, confirmation via email or text.(gov.uk)
Key Deadlines & Who Should Register
- 5 October 2026: Deadline for those who are new to Self Assessment for the 2025–26 tax year to register. Anyone who fails to register by this date may incur a penalty.(gov.uk)
- This includes sole traders earning over £1,000, individuals receiving untaxed income, or new partners in partnerships.(gov.uk)
- If you already registered but didn’t submit a return last year, you’ll need to reactivate your account.(gov.uk)
What You Must Know About Making Tax Digital for Income Tax (MTD for ITSA)
Aligned closely with the registration changes, there are important updates for those affected by Making Tax Digital for Income Tax Self Assessment:
- If you are a sole trader or landlord with qualifying income over £50,000 in 2024–25, you must use MTD for ITSA starting 6 April 2026.(gov.uk)
- HMRC will auto-sign up those who haven’t done so by themselves and will contact them once enrolled.(gov.uk)
- The penalties regime has changed, and compliance now includes quarterly updates of self-employment and property income.(gov.uk)
Examples & Action Plan
| Scenario | What Action to Take | Why It Matters |
|---|---|---|
| You started a limited side business in 2025-26 with income >£1,000 | Register via the new online Self Assessment service before 5 October 2026 | To avoid penalties and ensure you receive your UTR in time |
| You have property or business income over £50,000 | Ensure your software supports MTD, begin quarterly submissions | To meet legal requirement from 6 April 2026 under ITSA |
| You’re unsure about needing to file | Use HMRC’s online checking tool | Helps clarify obligations; missing registration can lead to fines |
Practical Tips to Prepare Now
- Choose compatible accounting software if required under MTD. Most cloud-based systems now support the quarterly updates needed.
- If you’re new, register early to allow time for data gathering and familiarisation with the system. Getting your UTR quickly helps avoid delays.
- Keep digital records of all income and expenses—receipts, invoices, and bank statements should be organised in software that can produce summaries every 3 months.
- If you work with an agent, ensure they’re clear on your obligations for MTD and registration deadlines.
Bottom Line
If you haven’t yet registered or determined whether you fall under Making Tax Digital rules, act before 5 October 2026. This is a period of transition—digitalisation, faster turnaround, stronger enforcement. Better to be prepared now than scrambling later.