2018 Business Tax Deadlines for 2017 Tax Filing

Your business’s tax return deadline is based on its entity type, whether or not you plan on filing an extension, and if there are any weekend or federal holidays in the picture.

The table below details when each type of business entity needs to file 2017 taxes in 2018 (using the calendar year)

 Entity Type Tax Deadline Due Date
Original deadline for partnerships (Form 1065) and S Corporations (Form 1120S) March 15, 2018
Original deadline for C Corporations (Form 1120) and individuals (Form 1040) April 17, 2018
Original deadline for exempt organizations (Form 990) May 15, 2018
Final deadline for partnerships and S Corporations (with extension) September 17, 2018
Final deadline for C Corporations and individuals (with extension) October 15, 2018
Final deadline for exempt organizations (with extension) August 15, 2018

 

Typically, the tax return due date for flow-through entities is the fifteenth day of the third month of the company’s fiscal year. So the S Corporation and LLC tax return due date in 2018 will fall on March 15 (for partnerships that follow the calendar year). The extended due date for flow-through taxes will be September 17, 2018.