« All Events Event Series Event Series: Form 1041ES – 1st Qtr Form 1041ES – 1st Qtr April 15, 2026 « Forms 1065 & 1120S (Calendar Year) unless an extension filed 1st Qtr Payroll Due » Add to calendar Google Calendar iCalendar Outlook 365 Outlook Live Details Date: April 15, 2026 Series: Form 1041ES – 1st Qtr