March 16, 2015
Deadline for corporate tax returns (Forms 1120, 1120A, and 1120S) for the year 2014, or to request automatic 6-month extension of time to file (Form 7004) for corporations who use the calendar year as their tax year. (The normal deadline for corporate returns is March 15th, but this falls on a Sunday, so the deadline is pushed to the next business day, which is Monday, March 16th.)