These are the deadlines for the year 2023:
*There is no Quarterly Income Tax Return (1701Q/1702Q) for the 4th Quarter of the year. This is covered by the Annual Income Tax Return (1701/1702RT) as well.
Do note that the above dates are subject to change. The dates will be updated in Taxumo as they change so you're always up to date if you use Taxumo.