Tax Diary April & May 2021 9 April 2021 Share 19 April 2021 - PAYE and NIC deductions due for month ended 5 April 2021. (If you pay your tax electronically the due date is 22 April 2021) 19 April 2021 - Filing deadline for the CIS300 monthly return for the month ended 5 April 2021. 19 April 2021 - CIS tax deducted for the month ended 5 April 2021 is payable by today. 30 April 2021 – 2019-20 tax returns filed after this date will be subject to an additional £10 per day late filing penalty. 1 May 2021 - Due date for Corporation Tax due for the year ended 30 July 2020. 19 May 2021 - PAYE and NIC deductions due for month ended 5 May 2021. (If you pay your tax electronically the due date is 22 May 2021). 19 May 2021 - Filing deadline for the CIS300 monthly return for the month ended 5 May 2021. 19 May 2021 - CIS tax deducted for the month ended 5 May 2021 is payable by today. 31 May 2021 - Ensure all employees have been given their P60s for the 2020-21 tax year. CIS300corporation taxFiling DeadlineNICP60PAYEtaxtax returns CONTACT US