C Corp Tax Extension Deadline 2025. 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, 2025—unless you use your own fiscal calendar, in which case it’s due on the 15th of the 4th month. You could have submitted form 4868 to.

The same goes for businesses: You could have submitted form 4868 to.