Corporations file Schedule M-3 (Form 1120) to answer questions about their financial statements and reconcile financial statement net income (loss) Where to file your taxes for Form 1120-S ; A foreign country or U.S. possession.Report and pay FUTA tax if the corporation either: If you are an employer, you must file a quarterly Form 941 to report. Find out what takes place in the formation of a corporation and the resulting tax responsibilities and required forms. If "Yes," complete and attach Form 8991. 23. General information. Purpose of Form IT-204. The general corporation tax (GCT) only applies to subchapter S corporations and qualified subchapter S subsidiaries under the US Internal Revenue Code.