Feb 05 What are the due dates for tax returns? A What are the due dates for tax returns? The answers below will be the same year to year unless the date falls on a holiday or weekend. If that is the case the due date will be the following weekday. Return Type Original Due Date Extended Due Date Partnerships, S-Corporations 3/15 9/15 C-Corporations (Calendar Year) 4/15 9/15 C-Corporations (Fiscal Year-End other than 6/30 and 12/31) 15th day of the 4th month after year-end 15th day of the 10th month after year-end C-Corporations (Fiscal Year-End 6/30) 9/15 4/15 Individuals, FinCen Report 114 4/15 10/15 Trusts & Estates 4/15 9/30 Exempt Organizations (Form 990) 5/15 11/15 W-2’s, 1099-MISC 1/31 N/A Permalink