Corporation Tax Tax Diary CIS Corporation Tax PAYE Tax diary Tax Diary October/November 2021 1 October 2021 – Due date for Corporation Tax due for the year ended 31 December 2020. 19 October 2021 – PAYE and NIC deductions due for month ended 5 October 2021. (If you pay your tax electronically the due date is 22 October 2021.)…