Self Assessment Deadlines 2026-27: Key HMRC Dates
Self Assessment deadlines for 2025-26 and 2026-27: registration, paper and online returns, payments on account, MTD quarterly updates and late filing penalties.
Quick answer: The main Self Assessment deadlines are 5 October (register), 31 October (paper return), 31 January (online return, balancing payment and first payment on account) and 31 July (second payment on account). For the 2025-26 tax year, the online return and payment are due on 31 January 2027.
Self Assessment is the system HMRC uses to collect Income Tax and National Insurance from the self-employed, partners, landlords and anyone with untaxed income. The dates repeat every year, but they apply to different tax years at the same time, which causes confusion. On top of that, Making Tax Digital for Income Tax added quarterly deadlines for some sole traders and landlords from April 2026. This guide lays out every key date for the 2025-26 and 2026-27 tax years, explains payments on account, and shows what happens if you miss a deadline. It is general information, not tax advice. HMRC's official list is on GOV.UK at Self Assessment tax returns: deadlines.
What are the Self Assessment deadlines for 2025-26?
The 2025-26 tax year ran from 6 April 2025 to 5 April 2026. Its return is the one most people are filing this winter.
| Date | What is due |
|---|---|
| 31 July 2026 | Second payment on account for 2025-26 |
| 5 October 2026 | Register for Self Assessment if you need to file for 2025-26 for the first time |
| 31 October 2026 | Paper tax return for 2025-26 |
| 30 December 2026 | File online by this date if you want tax under £3,000 collected through your PAYE tax code |
| 31 January 2027 | Online tax return for 2025-26; balancing payment for 2025-26; first payment on account for 2026-27 |
| 31 July 2027 | Second payment on account for 2026-27 |
If a deadline falls on a weekend, HMRC still treats the stated date as the deadline for online filing, so do not count on extra days. If you have not filed before, our step-by-step Self Assessment tax return guide covers the forms.
What are the Self Assessment deadlines for 2026-27?
The 2026-27 tax year runs from 6 April 2026 to 5 April 2027. The annual dates follow the same pattern, one year later:
| Date | What is due |
|---|---|
| 31 January 2027 | First payment on account for 2026-27 |
| 31 July 2027 | Second payment on account for 2026-27 |
| 5 October 2027 | Register if you first need to file for 2026-27, such as new self-employment started after 6 April 2026 |
| 31 October 2027 | Paper return for 2026-27 |
| 31 January 2028 | Online return (or final declaration under MTD) and balancing payment for 2026-27; first payment on account for 2027-28 |
What are the Making Tax Digital for Income Tax deadlines?
From 6 April 2026, sole traders and landlords with qualifying income (gross self-employment plus property income) over £50,000 must use Making Tax Digital for Income Tax. The threshold falls to £30,000 from April 2027 and £20,000 from April 2028, based on income in earlier years. Those within MTD keep digital records and send quarterly updates through compatible software, then a final declaration instead of the usual return.
| Quarter (standard periods) | Update due |
|---|---|
| 6 April to 5 July 2026 | 7 August 2026 |
| 6 July to 5 October 2026 | 7 November 2026 |
| 6 October 2026 to 5 January 2027 | 7 February 2027 |
| 6 January to 5 April 2027 | 7 May 2027 |
| Final declaration for 2026-27 | 31 January 2028 |
Quarterly updates are summaries of income and expenses, not tax payments. Payment dates stay the same: 31 January and 31 July. Taxpayers can opt to use calendar quarters (ending on the last day of each month) instead. Full details are in our guide to Making Tax Digital for Income Tax.
How do payments on account work?
Payments on account are advance payments towards your next tax bill. HMRC asks for them if your last Self Assessment bill was £1,000 or more, unless more than 80% of your tax was collected at source. Each payment is half of the previous year's bill (Income Tax plus Class 4 National Insurance), due on 31 January and 31 July. Any difference is settled with a balancing payment the following 31 January.
Payments on account are the reason the first January bill after you go self-employed is often a shock: you pay the full previous year's tax plus half of it again in advance. Our guide to HMRC payments on account explains how to reduce them if your income has dropped.
Worked example: a freelancer's first two years
Amir starts freelancing as a copywriter on 1 June 2025, leaving his job. He registers for Self Assessment in August 2026 (before the 5 October 2026 deadline) and receives his UTR. His figures are illustrative and use a combined Income Tax and Class 4 National Insurance bill:
| Date | Payment | Amount |
|---|---|---|
| 31 January 2027 | Balancing payment for 2025-26 (whole year's self-employment tax) | £4,800 |
| 31 January 2027 | First payment on account for 2026-27 (50% of £4,800) | £2,400 |
| 31 July 2027 | Second payment on account for 2026-27 | £2,400 |
| 31 January 2028 | Balancing payment if 2026-27 tax is £7,000 (£7,000 minus £4,800 paid) | £2,200 |
| 31 January 2028 | First payment on account for 2027-28 (50% of £7,000) | £3,500 |
Amir pays £7,200 in January 2027 alone. Setting aside a fixed share of every invoice payment from the start avoids that cash crunch. If he cannot pay in full, he can ask about an HMRC Time to Pay arrangement.
What are the penalties for missing Self Assessment deadlines?
For taxpayers not yet within Making Tax Digital for Income Tax, the familiar penalties apply:
| How late | Late filing penalty | Late payment penalty |
|---|---|---|
| 1 day | £100 fixed penalty | Interest starts |
| 30 days | 5% of tax unpaid | |
| 3 months | £10 a day for up to 90 days (maximum £900) | |
| 6 months | 5% of tax due or £300, whichever is higher | A further 5% of tax unpaid |
| 12 months | Another 5% or £300, whichever is higher (more in serious cases) | A further 5% of tax unpaid |
People within MTD for Income Tax move to the newer points-based late submission penalties and the late payment penalty model already used for VAT. Read Self Assessment late penalties for the detail and for how to appeal with a reasonable excuse.
How to never miss a Self Assessment deadline
- Register early. As soon as you start trading, register and get your UTR number. See how to register as self-employed.
- Put all dates in your calendar with reminders two weeks before: 31 January, 31 July, 5 October and, if you are within MTD, the four quarterly update dates.
- Keep records monthly. Record each invoice and expense as it happens rather than at year end; our guide to allowable expenses for the self-employed shows what to track.
- Set aside tax from every payment, typically 20% to 30% depending on your income level, in a separate savings account.
- File early. Filing in the summer or autumn tells you the bill months in advance, even though payment is not due until January.
- Check your HMRC online account for payment references and statements before paying.
Which Self Assessment deadlines apply to you?
Not everyone has every date. Use this quick guide to see which ones matter for your situation:
| Your situation | Dates to watch |
|---|---|
| Newly self-employed this tax year | 5 October after the tax year ends (register), then 31 January (file and pay, often with a first payment on account) |
| Established sole trader, income £50,000 or less, not in MTD | 31 January and 31 July payments; 31 January online return |
| Sole trader or landlord with qualifying income over £50,000 | Quarterly MTD updates on the 7th of August, November, February and May; final declaration 31 January; payments 31 January and 31 July |
| Employee with small side income under £1,000 | Possibly none: the trading allowance may cover it |
| Employee owing under £3,000 who wants it collected through PAYE | 30 December online filing |
| Paper filer | 31 October |
Self-employed people also pay Class 4 National Insurance through Self Assessment, so it is included in the same 31 January and 31 July payments. Class 2 contributions are no longer compulsory for most self-employed people, but you can still pay voluntarily to protect State Pension entitlement where your profits are low.
The figures you report all start with your sales records. If your invoices are numbered in sequence and dated correctly, adding up turnover for the tax year (or a quarter, under MTD) takes minutes. A simple routine is to issue every invoice from one tool, such as our invoice generator, and log it in a spreadsheet or bookkeeping app straight away.
Common Self Assessment deadline mistakes
- Thinking 31 January is only a filing deadline and forgetting it is also a payment date.
- Forgetting the first payment on account in your first full year of self-employment.
- Missing the 5 October registration deadline for new self-employment.
- Filing on paper after 31 October, which triggers a penalty even though the online deadline is later.
- Assuming no penalty applies when no tax is due. The £100 late filing penalty still applies.
- Confusing MTD quarterly updates with tax payments, or missing them entirely.
Self Assessment deadlines are predictable once you map them out: register by 5 October, file online and pay by 31 January, pay the second instalment by 31 July, and add the quarterly MTD dates if they apply to you. Clear, numbered invoices make the yearly figures easy to total. Our free invoice generator creates professional invoices for sole traders with no sign-up and downloads them as a PDF built in your browser.
Frequently asked questions
What is the deadline for the 2025-26 Self Assessment tax return?
For the 2025-26 tax year, which ran from 6 April 2025 to 5 April 2026, the paper return deadline is 31 October 2026 and the online return deadline is 31 January 2027. Any tax owed for 2025-26, plus the first payment on account for 2026-27 if one applies, must also be paid by 31 January 2027. Late filing penalties start the day after the deadline.
When do I need to register for Self Assessment?
You must tell HMRC by 5 October following the end of the tax year in which you first need to file. For income in the 2025-26 tax year, that was 5 October 2026. For new self-employment that starts during the 2026-27 tax year, the registration deadline is 5 October 2027. Registering gives you a Unique Taxpayer Reference, which you need to file the return.
Can I pay my tax through my PAYE tax code instead?
Possibly. If you owe less than £3,000, already pay tax through PAYE as an employee or pensioner, and file your online return by 30 December, HMRC can collect the amount through your tax code over the following tax year. This spreads the payment rather than paying a lump sum on 31 January. It does not apply if you file on paper after 31 October.
What happens if I miss the 31 January deadline?
If you are not within Making Tax Digital for Income Tax, a late online return brings an immediate £100 penalty, even if no tax is due. After three months, daily penalties of £10 apply for up to 90 days. After six and twelve months, further penalties of 5% of the tax due or £300, whichever is higher, apply. Interest and late payment penalties are charged separately on unpaid tax.
What are the Making Tax Digital quarterly update deadlines?
Sole traders and landlords within Making Tax Digital for Income Tax send quarterly updates through compatible software. Using standard quarters, updates are due on 7 August, 7 November, 7 February and 7 May. For 2026-27 that means 7 August 2026, 7 November 2026, 7 February 2027 and 7 May 2027, with the final declaration due by 31 January 2028.
Who has to file a Self Assessment tax return?
You generally need to file if you were self-employed with gross trading income above £1,000, a partner in a business partnership, had untaxed income such as rental income or certain savings or investment income above allowances, or received income from abroad. People with income over certain levels or who need to pay the High Income Child Benefit Charge may also need to file. HMRC's online checker confirms whether you do.
Can I get an extension on my Self Assessment deadline?
There is no general extension. HMRC may accept a late return without a penalty if you have a reasonable excuse, such as a serious illness, the death of a close relative or an unexpected HMRC system failure, provided you file as soon as the excuse ends. If HMRC issues a notice to file after 31 October, you have three months from the date of the notice to file.
Do I have to make payments on account?
You make payments on account if your last Self Assessment bill was £1,000 or more, unless more than 80% of your tax was already collected at source, for example through PAYE. Each payment is half of the previous year's bill and is due on 31 January and 31 July. You can apply to reduce them if you expect lower income this year.
Invoice Creator Editorial Team
Guides on invoicing, cash flow and small-business finance from Invoice Creator, operated by Next Software Development Company. Content is reviewed for accuracy against the fields our own invoice generator produces.
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