Tax Return Filing Due Date date Dec 21 Dec 21 12:00 PM – 12:00 PM | Monday, December 21, 2026 Other Event Dates › Monday, September 21, 2026 Tuesday, October 20, 2026 Friday, November 20, 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.