Each date shown is the prescribed due date for filing the return or making the tax payment indicated. If any date falls on a Saturday, Sunday, or legal holiday, the return or payment is due on the next business day.
| May 15 | Income tax return due for prior calendar year (Form 990-PF or 990). Due date for exempt organizations to file Form 8868, Application for Three Month Extension of Time. |
| Jun. 30 | Due date for Illinois Charitable Organization Annual Report (AG 990-IL) or due date for submitting letter requesting additional 60 day extension with $15 annual report filing fee. |
| Aug. 15 | Due date for additional (not automatic) three month extension of time (Form 8868, page 2). |
| Nov. 15 | Second extended due date for calendar tax exempt organizations that received second extension to file prior year income tax return. |
Some Not-for-Profit Organizations may be able to elect a year end other than December 31; the above dates, which are for calendar-year entities, should be modified in such cases.