- 21 December 2020 (23rd December 2020 for online payment and filing):
Corporation Tax Return CT 1 and final payment for companies with accounting periods ending 31 March 2020
- 21 December 2020 (23rd December 2020 for online payment and filing):
Preliminary Corporation Tax due (where liability is less than €200,000) for accounting periods ending 31 January 2021
- 21 December 2020:
Form 46G for companies with accounting periods ending 31 March 2020
