Tax Diary August/September 2025

1 August 2025 – Due date for corporation tax due for the year ended 31 October 2024.

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

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

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

1 September 2025 – Due date for corporation tax due for the year ended 30 November 2024.

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

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

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