Corporate Tax Return Due Date 2024. If you’re a c corporation or llc electing to file your taxes as one for 2023, your corporate tax return is due on april 15th, 2024—unless you use your own fiscal calendar, in which case it’s due on the 15th of the 4th month following the end of your tax year. Return filing due date for first tax period.

1 january 2025 to 31 december 2025: Return filing due date for first tax period.