The IRS will begin accepting 2013 business tax returns on Monday, Jan. 13, 2014. This start date applies to both electronically-filed and paper-filed returns.

Business returns include any return that posts on the IRS Business Master File (BMF). BMF returns include a variety of income tax and information returns such as Form 1120 filed by corporations, Form 1120S filed by S corporations, Form 1065 filed by partnerships and Form 1041, the return filed by estates and trusts. It also includes various excise and payroll tax returns, such as Form 720, Form 940, Form 941 and Form 2290. The IRS expects to be able to begin processing any of these business returns on Jan. 13.

The Jan. 13 start date does not apply to unincorporated small businesses that report their income on Form 1040. The start date for all 1040 filers is Jan. 31, 2014. Although the IRS encourages these small businesses to begin preparing their returns now, it will not be able to accept these or any other individual returns or begin processing them until Jan. 31. This includes sole proprietors who file a Schedule C, landlords who file a Schedule E and farmers who file a Schedule F.