Corps & S Corps Form 1120 Due
Corporations: File Form 1120 for calendar year and pay any tax due. For automatic 6-month extension, file Form 7004 and deposit estimated tax.
S Corporations: File Form 1120S for calendar year and pay any tax due. Furnish a copy of Sch. K-1 to each shareholder. File Form 2553 to elect S Corporation status beginning with calendar year 2016