March 2
- Large employers and others must furnish Form 1095-B or Form 1095-C to employees.
March 15
- 2016 calendar-year S corporation Form 1120S income tax returns are due.
- 2016 calendar-year partnerships Form 1065 income tax returns are due.
March 31
- Forms 1095-B and 1095-C due to the IRS, if filing electronically. Employers who have 250 or more employees are required to file electronically.