March 15 – Corporations
File a 2010 calendar year income tax return (Form 1120 or 1120-A) and pay any tax due. If you need an automatic 6-month extension of time to file the return, file Form 7004, Application for Automatic Extension of Time To File Certain Business Income Tax, Information and Other Returns, and deposit what you estimate you owe. Filing this extension protects you from late filing penalties but not late payment penalties, so it is important that you estimate your liability and deposit it using the instructions on Form 7004.
March 15 – S-Corporation Election
File Form 2553, Election by a Small Business Corporation, to choose to be treated as an S corporation beginning with calendar year 2011. If Form 2553 is filed late, S treatment will begin with calendar year 2012.
March 15 – Electing Large Partnerships
Provide each partner with a copy of Schedule K-1 (Form 1065-B), Partner’s Share of Income (Loss) From an Electing Large Partnership, or a substitute Schedule K-1. This due date is effective for the first March 15 following the close of the partnership’s tax year. The due date of March 15 applies even if the partnership requests an extension of time to file the Form 1065-B by filing Form 7004.
March 31 – Electronic Filing of Forms 1098, 1099 and W-2G
If you file forms 1098, 1099, or W-2G electronically with the IRS, this is the final due date. This due date applies only if you file electronically (not paper forms). Otherwise, February 28 was the due date. The due date for giving the recipient these forms was January 31.
March 31 – Electronic Filing of Forms W-2
If you file forms W-2 for 2010 electronically with the IRS, this is the final due date. This due date applies only if you electronically file. Otherwise, the due date was February 28. The due date for giving the recipient these forms was January 31.
March 31 – Large Food and Beverage Establishment Employers
If you file forms 8027 for 2010 electronically with the IRS, this is the final due date. This due date applies only if you file electronically. Otherwise, February 28 was the due date.