Tax Diary

1 January 2026 – Due date for Corporation Tax due for the year ended 31 March 2025

19 January 2026 – PAYE and NIC deductions due for month ended 5 January 2026. (If you pay your tax electronically the due date is 22 January 2026).

19 January 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 January 2026.

19 January 2026 – CIS tax deducted for the month ended 5 January 2026 is payable by today.

31 January 2026 – Last day to file 2024-25 self-assessment tax returns online.

31 January 2026 – Balance of self-assessment tax owing for 2024-25 due to be settled on or before today unless you have elected to extend this deadline by formal agreement with HMRC. Also due is any first payment on account for 2025-26.

1 February 2026 – Due date for Corporation Tax payable for the year ended 30 April 2025.

19 February 2026 – PAYE and NIC deductions due for month ended 5 February 2026. (If you pay your tax electronically the due date is 22 February 2026)

19 February 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 February 2026.

19 February 2026 – CIS tax deducted for the month ended 5 February 2026 is payable by today.

1 December 2025 – Due date for Corporation Tax payable for the year ended 28 February 2025.

19 December 2025 – PAYE and NIC deductions due for month ended 5 December 2025. (If you pay your tax electronically the due date is 22 December 2025).

19 December 2025 – Filing deadline for the CIS300 monthly return for the month ended 5 December 2025. 

19 December 2025 – CIS tax deducted for the month ended 5 December 2025 is payable by today.

30 December 2025 – Deadline for filing 2024-25 self-assessment tax returns online to include a claim for under payments to be collected via tax code in 2026-27.

1 January 2026 – Due date for Corporation Tax due for the year ended 31 March 2025.

19 January 2026 – PAYE and NIC deductions due for month ended 5 January 2026. (If you pay your tax electronically the due date is 22 January 2026).

19 January 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 January 2026. 

19 January 2026 – CIS tax deducted for the month ended 5 January 2026 is payable by today.

31 January 2026 – Last day to file 2023-24 self-assessment tax returns online.

31 January 2026 – Balance of self-assessment tax owing for 2024-25 due to be settled on or before today unless you have elected to extend this deadline by formal agreement with HMRC. Also due is any first payment on account for 2025-26.

1 October 2020 – Due date for Corporation Tax due for the year ended 31 December 2019.

19 October 2020 – PAYE and NIC deductions due for month ended 5 October 2020. (If you pay your tax electronically the due date is 22 October 2020.)

19 October 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 October 2020. 

19 October 2020 – CIS tax deducted for the month ended 5 October 2020 is payable by today.

31 October 2020 – Latest date you can file a paper version of your 2020 Self-Assessment tax return.

1 November 2020 – Due date for Corporation Tax due for the year ended 31 January 2020.

19 November 2020 – PAYE and NIC deductions due for month ended 5 November 2020. (If you pay your tax electronically the due date is 22 November 2020.)

19 November 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 November 2020. 

19 November 2020 – CIS tax deducted for the month ended 5 November 2020 is payable by today.

1 September 2020 – Due date for Corporation Tax due for the year ended 30 November 2019.

19 September 2020 – PAYE and NIC deductions due for month ended 5 September 2020. (If you pay your tax electronically the due date is 22 September 2020)

19 September 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 September 2020. 

19 September 2020 – CIS tax deducted for the month ended 5 September 2020 is payable by today.

1 October 2020 – Due date for Corporation Tax due for the year ended 31 December 2019.

19 October 2020 – PAYE and NIC deductions due for month ended 5 October 2020. (If you pay your tax electronically the due date is 22 October 2020.)

19 October 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 October 2020. 

19 October 2020 – CIS tax deducted for the month ended 5 October 2020 is payable by today.

31 October 2020 – Latest date you can file a paper version of your 2020 self-assessment tax return.

1 August 2020 – Due date for Corporation Tax due for the year ended 31 October 2019.

19 August 2020 – PAYE and NIC deductions due for month ended 5 August 2020. (If you pay your tax electronically the due date is 22 August 2020)

19 August 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 August 2020. 

19 August 2020 – CIS tax deducted for the month ended 5 August 2020 is payable by today.

1 September 2020 – Due date for Corporation Tax due for the year ended 30 November 2019.

19 September 2020 – PAYE and NIC deductions due for month ended 5 September 2020. (If you pay your tax electronically the due date is 22 September 2020)

19 September 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 September 2020. 

19 September 2020 – CIS tax deducted for the month ended 5 September 2020 is payable by today.

1 July 2020 – Due date for Corporation Tax due for the year ended 30 September 2019.

6 July 2020 – Complete and submit forms P11D return of benefits and expenses and P11D(b) return of Class 1A NICs.

19 July 2020 – Pay Class 1A NICs (by the 22 July 2020 if paid electronically).

19 July 2020 – PAYE and NIC deductions due for month ended 5 July 2020. (If you pay your tax electronically the due date is 22 July 2020)

19 July 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 July 2020. 

19 July 2020 – CIS tax deducted for the month ended 5 July 2020 is payable by today.

31 July 2020 – Self-assessment second payment on account for 2019-20 is due. The government has announced measures that will allow many tax payers to delay this payment until January 2021, if they wish. 

1 August 2020 – Due date for Corporation Tax due for the year ended 31 October 2019.

19 August 2020 – PAYE and NIC deductions due for month ended 5 August 2020. (If you pay your tax electronically the due date is 22 August 2020)

19 August 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 August 2020. 

19 August 2020 – CIS tax deducted for the month ended 5 August 2020 is payable by today.
 

1 June 2020 – Due date for Corporation Tax due for the year ended 31 August 2019.

19 June 2020 – PAYE and NIC deductions due for month ended 5 June 2020. (If you pay your tax electronically the due date is 22 June 2020)

19 June 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 June 2020. 

19 June 2020 – CIS tax deducted for the month ended 5 June 2020 is payable by today.

1 July 2020 – Due date for Corporation Tax due for the year ended 30 September 2019.

6 July 2020 – Complete and submit forms P11D return of benefits and expenses and P11D(b) return of Class 1A NICs.

19 July 2020 – Pay Class 1A NICs (by the 22 July 2020 if paid electronically).

19 July 2020 – PAYE and NIC deductions due for month ended 5 July 2020. (If you pay your tax electronically the due date is 22 July 2020)

19 July 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 July 2020. 

19 July 2020 – CIS tax deducted for the month ended 5 July 2020 is payable by today.

1 May 2020 – Due date for Corporation Tax due for the year ended 30 July 2019.

19 May 2020 – PAYE and NIC deductions due for month ended 5 May 2020. (If you pay your tax electronically the due date is 22 May 2020).

19 May 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 May 2020. 

19 May 2020 – CIS tax deducted for the month ended 5 May 2020 is payable by today.

31 May 2020 – Ensure all employees have been given their P60s for the 2019-20 tax year.

1 June 2020 – Due date for Corporation Tax due for the year ended 31 August 2019.

19 June 2020 – PAYE and NIC deductions due for month ended 5 June 2020. (If you pay your tax electronically the due date is 22 June 2020)

19 June 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 June 2020. 

19 June 2020 – CIS tax deducted for the month ended 5 June 2020 is payable by today.

1 April 2020 – Due date for Corporation Tax due for the year ended 30 June 2019.

19 April 2020 – PAYE and NIC deductions due for month ended 5 April 2020. (If you pay your tax electronically the due date is 22 April 2020).

19 April 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 April 2020. 

19 April 2020 – CIS tax deducted for the month ended 5 April 2020 is payable by today.

30 April 2020 – 2018-19 tax returns filed after this date will be subject to an additional £10 per day late filing penalty.

1 May 2020 – Due date for Corporation Tax due for the year ended 30 July 2019.

19 May 2020 – PAYE and NIC deductions due for month ended 5 May 2020. (If you pay your tax electronically the due date is 22 May 2020).

19 May 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 May 2020. 

19 May 2020 – CIS tax deducted for the month ended 5 May 2020 is payable by today.

31 May 2020 – Ensure all employees have been given their P60s for the 2019-20 tax year.

1 March 2020 – Due date for Corporation Tax due for the year ended 31 May 2019.

2 March 2020 – Self assessment tax for 2019/19 paid after this date will incur a 5% surcharge.

19 March 2020 – PAYE and NIC deductions due for month ended 5 March 2020. (If you pay your tax electronically the due date is 22 March 2020)

19 March 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 March 2020. 

19 March 2020 – CIS tax deducted for the month ended 5 March 2020 is payable by today.

1 April 2020 – Due date for Corporation Tax due for the year ended 30 June 2019.

19 April 2020 – PAYE and NIC deductions due for month ended 5 April 2020. (If you pay your tax electronically the due date is 22 April 2020)

19 April 2020 – Filing deadline for the CIS300 monthly return for the month ended 5 April 2020. 

19 April 2020 – CIS tax deducted for the month ended 5 April 2020 is payable by today.

30 April 2020 – 2018-19 tax returns filed after this date will be subject to an additional £10 per day late filing penalty.