Partnerships and corporations have different standards for filing an information return or income tax return.

• Partnerships file an information return on Form 1065, U.S. Return of Partnership Income.
• A domestic partnership must file an information return, unless it neither receives gross income nor pays or incurs any amount treated as a deduction or credit for federal income tax purposes.
• A foreign partnership generally must file an information return if:
  • It has gross income effectively connected with the conduct of a trade or business within the United States,
  • It has gross income derived from sources in the United States, or
  • It is making an election, such as an election to amortize organization expenses.

Refer to the Instructions for Form 1065, U.S. Return of Partnership Income for exceptions to filing requirements.

• A domestic corporation must file Form 1120, U.S. Corporation Income Tax Return, whether it has taxable income or not, unless it's exempt from filing under section 501.
• A domestic corporation that is an S corporation must file Form 1120-S, U.S. Income Tax Return for an S corporation.  
• A foreign corporation generally must file Form 1120-F, U.S. Income Tax Return of a Foreign Corporation, if during the tax year it:
  • Engages in a trade or business in the United States, even if it has no income from sources in the United States from that trade or business, and whether or not income from that trade or business is exempt from U.S. tax under a tax treaty,
  • Has income, gains or losses treated as if effectively connected with the conduct of a U.S. trade or business, or
  • Doesn't engage in a trade or business in the United States but has income from U.S. source, and the withholding of tax at source under Chapter 3 of the Internal Revenue Code didn't fully satisfy its tax liability.
  • Was, or had a branch that was, a qualified derivatives dealer.

Refer to the Instructions for Form 1120-F, U.S. Income Tax Return of a Foreign Corporation for other reasons a foreign corporation must file Form 1120-F and exceptions to filing requirements.