Tax Diary May/June 2026

1 May 2026 – Due date for corporation tax due for the year ended 30 July 2025.

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

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

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

31 May 2026 – Ensure all employees have been given their P60s for the 2025/26 tax year.

1 June 2026 – Due date for corporation tax due for the year ended 31 August 2025.

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

19 June 2026 – Filing deadline for the CIS300 monthly return for the month ended 5 June 2024. 

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