You must file
Form IL-1120-ST, Small Business Corporation Replacement Tax Return, if you are a small business corporation (S corp), as defined in Internal Revenue Code (IRC), Section 1361(a), that
- has net income or loss as defined under the Illinois Income Tax Act (IITA) or
- is qualified to do business in the state of Illinois and is required to file U.S. Form 1120S (regardless of net income or loss).
required to report and pay pass-through withholding on behalf of your nonresident shareholders if they have not provided Form IL-1000-E, Certificate of Exemption for Pass-through Withholding, to you. Individuals cannot claim the exemption from pass-through withholding by filing Form IL-1000-E. For tax years ending:
On or after December 31, 2014, you must include these amounts on your Form IL-1120-ST and Schedule B, Partners' or Shareholders' Information. You must also complete and retain a copy of
Schedule K-1-P(3), Pass-through Withholding Calculation for Nonresident Members, for each of your nonresident shareholders.
Note: If you are a fiscal-year filer and file during a year with a tax rate change, you will be required to complete Schedule K-1-P(3)-FY, Pass-through Withholding Calculation for Nonresident Members (for Fiscal Filers), instead. See the
Schedule K-1-P(1) Instructions for more information.
Before December 31, 2014, you must file Form IL-1023-C, Composite Income and Replacement Tax Return, or Form IL-1000, Pass-through Entity Payment Income Tax Return.
Note: Prior year forms and instructions for each tax type can be found by clicking the "Prior Years" link on our
Business Tax Forms page and selecting the corresponding year.
IL-1120-ST Instructions for due dates and filing requirements.