Tax Return Filing Due Date date Sep 21 Sep 21 12:00 PM – 12:00 PM | Monday, September 21, 2026 Other Event Dates › Tuesday, October 20, 2026 Friday, November 20, 2026 Monday, December 21, 2026 Wednesday, January 20, 2027 File Online! Keep track of Tax Return Due Dates and never miss a due date again! Click here to enjoy the convenience of online filing and payment.