HMRC's faster Self Assessment sign-up is live — register before 5 October
A rebuilt online registration means new Self Assessment customers get their tax reference in days, not weeks — but the 5 October deadline hasn't moved.
What happened
HMRC has launched an improved online registration service for Self Assessment, published 9 September 2026 (HMRC announcement). Forms now come pre-populated with your existing details, let you save and return without losing data, and confirm by email or text the moment registration is complete. More than 640,000 customers registered for Self Assessment in the 12 months to 31 March 2026.
What it means for you
The old process could leave you waiting up to 15 days for your Unique Taxpayer Reference (UTR) to arrive by post, time you need to actually complete your return before the 31 January 2027 filing deadline. Under the new service, your UTR lands in your online account within 72 hours. If you're newly self-employed with gross income over £1,000, became a partner in a business partnership, or received untaxed income over £2,500, this deadline applies to you. If you no longer need to file (for example, you've stopped trading), tell HMRC now — otherwise a return is still expected and a late-filing penalty can follow.
What you can do this week
Not sure if you need to register? Use HMRC's free online checker first. If you do, register via GOV.UK through your Personal Tax Account before 5 October.
- ✓Check whether you need to file: HMRC's free online checker.
- ✓If yes, register via GOV.UK through your Personal Tax Account (Government Gateway or GOV.UK One Login) before 5 October.
- ✓Already registered but didn't file for 2024–25 and need to file for 2025–26? Reactivate your account before you can submit this year's return.
Self Assessment sign-ups
Source: HMRC, 12 months to 31 March 2026
Common questions
What happens if I miss the 5 October deadline?
If you needed to register as newly self-employed, as a new partner, or for other new taxable income in 2025–26 and miss 5 October, HMRC can issue a penalty even before your tax return itself is due. Registering late doesn't move your 31 January 2027 filing and payment deadline either.
Do I need to register if I earned under £1,000 from a side hustle?
No. The £1,000 trading allowance means self-employment income under that threshold doesn't need to be declared or taxed, so registration isn't required for that income alone.
I'm already registered but didn't file last year. Do I need to do anything?
Yes. If you're registered but didn't submit a return for 2024–25 and need to file for 2025–26, you'll need to reactivate your account before you can submit this year's return.
What changed
- 21 Oct 2026: The 5 October 2026 deadline has passed. Missed it? Read: Missed HMRC's 5 October sign-up? Register now, pay by 31 January
Luca Bonura started selling online at 17 and funded his first business with 4:30am shifts in a bakery. He built his own product brand, watched it fail, and rebuilt as a freelance performance marketer for everyone from small shops to HelloFresh. Seeing how hard growth is even for people inside the industry, he founded Adlarion. He writes The Small Business Digest in plain English: the news he wished he'd had when starting out.
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