1 May 2019 – Due date for Corporation Tax due for the year ended 30 July 2018. 19 May 2019 – PAYE and NIC deductions due for month ended 5 May 2019. (If you pay your tax electronically the due date is 22 May 2019) 19 May 2019 – Filing deadline for the CIS300 monthly return for the month ended 5 May 2019.  19 May 2019 – CIS tax deducted for the month ended 5 May 2019 is payable by today. 31 May 2019 – Ensure all employees have been given their P60s for the 2018-19 tax year. 1 June 2019 – Due date for Corporation Tax due for the year ended 31 August 2018. 19 June 2019 – PAYE and NIC deductions due for month ended 5 June 2019. (If you pay your tax electronically the due date is 22 June 2019) 19 June 2019 – Filing deadline for the CIS300 monthly return for the month ended 5 June 2019.  19 June 2019 – CIS tax deducted for the month ended 5 June 2019 is payable by today.