Guides › Public Services › Self Assessment Deadlines 2026 to 2027: Register, File and Pay
Self Assessment Deadlines 2026 to 2027: Register, File and Pay
For the 2025 to 2026 tax year, tell HMRC you need to file by 5 October 2026 if you are new to Self Assessment. Paper returns must reach HMRC by 31 October 2026, online returns are due by 31 January 2027, and any tax owed must be paid by 31 January 2027. If you make payments on account, the second is due by 31 July.
At A Glance
Your Rights
What the rules say, with a link to the official source for each.
The Deadlines
Registering
Tell HMRC by 5 October 2026 if you have not sent a return before, or registered before but did not need to file for 2024 to 2025. source
Filing and Paying
Paper returns: by 11:59pm on 31 October 2026. Online returns: by 11:59pm on 31 January 2027. Pay what you owe by 11:59pm on 31 January 2027. Second payment on account: 31 July. source
If You Register Late
If you register after 5 October 2026, HMRC will send a letter or email with a return deadline 3 months from the date on it. You must still pay by 31 January 2027. source
Do You Need to File?
If you have extra income, for example from selling things online or renting out part of your home, check whether you need to tell HMRC. If HMRC writes asking you to send a return, you must send it by the deadline on the letter. source
Time Limits to Know
Miss a deadline and you can lose a right. Check the dates on your own paperwork.
- 5 October 2026Register for Self AssessmentIf you are new
- 31 January 2027File online and pay11:59pm
Steps to Take
Step 1 of 5
Check whether you need to file.
Step 2 of 5
Register by 5 October if you are new.
Step 3 of 5
Gather payslips, P60, bank interest and expenses records.
Step 4 of 5
File online before 31 January.
Step 5 of 5
Pay by 31 January, or set up a payment plan if you cannot.
(Tap the numbers to reveal steps)
Where to Go If It Is Not Put Right
Your options, in order, and when each one applies.
HMRC
Contact HMRC through your personal tax account, the HMRC app or the phone and post details on GOV.UK.
Your Personal Tax Account
Sign in on GOV.UK to check your tax code, income and letters.
Free Tax Help
TaxAid and Tax Help for Older People give free advice if your income is low.
Good to Know
Small things that make your complaint stronger.
Filing early does not mean paying early: you still have until 31 January to pay.
Scotland has its own Income Tax rates and bands. The rules on returns, penalties and HMRC complaints apply across the UK.
Want Help?
If you would like one of our team to look at your problem, our initial case review is free. We cannot guarantee any outcome and we do not give legal advice.
Lead reviewer
Luke Marley
Founder and Lead Reviewer
Luke founded CPUK in 2026 after seeing how hard it is for ordinary people to get problems with companies put right. He oversees our guides and checks them against official sources.
Research by Katie Burt, Co-founder and Operations Lead (17 years in the care sector, including managing services for vulnerable adults), and the CPUK Research Team. Researched with AI-assisted research tools, then checked and corrected by our team.
Last checked: 15 October 2026. We are not paid by the companies we write about. Adverts never affect our guidance. Read our editorial policy.
Sources and official links
- gov.uk/self-assessment-tax-returns/deadlines Checked 15 October 2026
- gov.uk/check-if-you-need-a-tax-return Checked 15 October 2026