Personal tax payments are due. Tax return filing deadline is April 30th unless you or your spouse have business income then filing deadline is June 15th.
Corporate: Payment Deadline is 2 months after your fiscal year end, unless eligible to claim the small business tax deduction then payment deadline is three months after the fiscal year end.
Corporate: Filing deadline is 6 months after the fiscal year end.
Trusts: Payment and filing deadline is March 31st (three months after the year end which is Dec 31st) unless a Graduated Rate Estate which is three months after the anniversary of the date of death for the first three tax years post death at which point it reverts to a calendar year with the typical March 31st deadline.
Tax Slips (T4, T4A, T5, …): Payment deadlines are as per usual (i.e. often Jan 15 for payroll amounts withheld)