Key UK Tax Deadlines: September 2026 to January 2027
It’s not unusual for business owners to fall behind on tax obligations simply because they can’t see what’s coming up. The next four months are busy for everyone, from sole traders to limited company directors. That’s why we’ve put together a complete list of the key deadlines for VAT, PAYE, Corporation Tax, CIS, Self Assessment and Making Tax Digital.
Read on to see which deadlines apply to you and how good planning can help you avoid missing them in future.
Why Is It Important to Know Upcoming Tax Deadlines?
Every business owner and self-employed professional is responsible for staying tax-compliant. Without year-round planning, you risk late payment penalties and interest charges.
Knowing your deadlines also helps with budgeting, keeps cash flow healthy and lets you plan ahead. Staying organised throughout the year reduces errors and spreads the admin more evenly. Missed deadlines can also reflect badly on a business and its directors, which can cause problems with suppliers or when applying for funding.
Tax Deadlines: 30 September 2026 to 31 January 2027
The end of the year is always a busy period. There are plenty of payment and reporting deadlines to meet, and it’s also when most businesses start planning for the year ahead.
A note on weekends: if a PAYE or CIS payment date falls on a weekend or bank holiday, your payment must reach HMRC by the last working day before it. We’ve flagged these dates below.
September 2026
| Date | Deadline |
| 30.09.26 | Company Tax Returns for accounting periods ending 30 September 2025. |
October 2026
| Date | Deadline |
| 01.10.26 | Corporation Tax payment for accounting periods ending 31 December 2025 (where instalment rules don’t apply). |
| 05.10.26 | Deadline to register for Self Assessment for the 2025/26 tax year if you haven’t filed a return before, for example if you became self-employed or started earning rental income. |
| 07.10.26 | VAT Returns and payments for periods ending 31 August 2026. |
| 14.10.26 | CT61 returns and payments for the quarter ending 30 September 2026. These cover payments made by companies where income tax should have been deducted, such as certain interest payments. |
| 19.10.26 | PAYE Settlement Agreement (PSA) tax and Class 1B NIC for 2025/26 paid by post. CIS returns and non-electronic PAYE payments are also due. |
| 22.10.26 | Electronic PSA payments for the 2025/26 tax year. |
| 22.10.26 | Electronic PAYE, NIC, student loan and CIS deduction payments for the tax month ending 5 October. |
| 28.10.26 | Autumn Budget 2026. The Chancellor, John Healey, will set out the government’s tax and spending plans, alongside the Office for Budget Responsibility’s economic forecast. Any changes announced could affect your tax planning for the year ahead. |
| 31.10.26 | Paper Self Assessment returns for the 2025/26 tax year. This date falls on a Saturday, so post returns well in advance. |
| 31.10.26 | Company Tax Returns for accounting periods ending 31 October 2025. |
November 2026
| Date | Deadline |
| 01.11.26 | Corporation Tax payment for accounting periods ending 31 January 2026 (where instalment rules don’t apply). |
| 07.11.26 | Making Tax Digital for Income Tax: second quarterly update (6 July to 5 October 2026). This applies to sole traders and landlords with qualifying income over £50,000. |
| 07.11.26 | VAT Returns and payments for periods ending 30 September 2026. |
| 19.11.26 | CIS monthly returns and non-electronic PAYE payments for the tax month ending 5 November. |
| 22.11.26 | Electronic PAYE, NIC, student loan and CIS deduction payments for the tax month ending 5 November. This date falls on a Sunday, so payment must arrive by Friday 20 November. |
| 30.11.26 | Company Tax Returns for accounting periods ending 30 November 2025. |
December 2026
| Date | Deadline |
| 01.12.26 | Corporation Tax payment for accounting periods ending 28 February 2026 (where instalment rules don’t apply). |
| 07.12.26 | VAT Returns and payments for periods ending 31 October 2026. |
| 19.12.26 | CIS returns and non-electronic PAYE payments for the tax month ending 5 December. This date falls on a Saturday, so payment must arrive by Friday 18 December. |
| 22.12.26 | Electronic PAYE, NIC, student loan and CIS deduction payments for the tax month ending 5 December. |
| 30.12.26 | Online Self Assessment deadline if you’re employed under PAYE and want HMRC to collect an underpayment of less than £3,000 through your tax code (conditions apply). |
| 31.12.26 | Company Tax Returns for accounting periods ending 31 December 2025. |
January 2027
| Date | Deadline |
| 01.01.27 | Corporation Tax payment for accounting periods ending 31 March 2026 (where instalment rules don’t apply). |
| 07.01.27 | VAT Returns and payments for periods ending 30 November 2026. |
| 14.01.27 | CT61 returns and payments for the quarter ending 31 December 2026. |
| 19.01.27 | CIS returns and non-electronic PAYE payments for the tax month ending 5 January. |
| 22.01.27 | Electronic PAYE, NIC, student loan and CIS deduction payments for the tax month ending 5 January. |
| 31.01.27 | Online Self Assessment returns for 2025/26 must be filed by 11:59pm. |
| 31.01.27 | Self Assessment balancing payment for 2025/26 and first payment on account for 2026/27. |
| 31.01.27 | Company Tax Returns for accounting periods ending 31 January 2026. |
Plan Ahead and Avoid the Last-Minute Rush
This list is extensive, but the key is not leaving anything until the last minute. Whether you’re managing Company Tax Returns, Self Assessment or ongoing payroll and VAT obligations, preparation makes all the difference. With the Autumn Budget on 28 October, it’s also a good time to review your position before any changes take effect.
Working with the Hysons team keeps you one step ahead. That means no nasty surprises and a solid compliance record with HMRC.
Get in touch to find out how we can help.