Here are the important dates you need to know regarding recent changes

Individuals : Federal & Quebec

Filing Deadline: April 30, 2021
Payment Due Date: April 30, 2021

Self-employed

Filing Deadline: June 15, 2021
Payment Due Date: September 1, 2021

Trusts with a tax year end of Dec 31, 2020

Filing Deadline: May 1, 2021
Payment Due Date: September 1, 2021

Corporations

Federal & Quebec with a filing due date after March 18 and before June 1
Filing Deadline: June 1, 2021
Payment Due Date: September 1, 2021
Alberta
6 months after year-end
Payment Due Date: August 31

Canadians with US tax filing

Filing Deadline: July 15