The following are major tax deadlines for March 2014.
- March 3 – Farmers and fishermen who did not make 2013 estimated tax payments are required to file 2013 tax returns and pay taxes in full.
- March 17 – 2013 calendar-year corporation income tax returns are due.
- March 17 – Deadline for calendar-year corporations to elect S corporation status for 2014.
- March 31 – Deadline for payors who file electronically to file 2013 information returns (such as 1099s) with the IRS.
- March 31 – Deadline for employers who file electronically to send copies of 2013 W-2s to the Social Security Administration.