In forming a corporation, prospective shareholders exchange money, property, or both, for the corporation's capital stock. A corporation generally takes the same deductions as a sole proprietorship to figure its taxable income. A corporation can also take special deductions. For federal income tax purposes, a C corporation is recognized as a separate taxpaying entity. A corporation conducts business, realizes net income or loss, pays taxes and distributes profits to shareholders.

The profit of a corporation is taxed to the corporation when earned, and then is taxed to the shareholders when distributed as dividends. This creates a double tax. The corporation does not get a tax deduction when it distributes dividends to shareholders. Shareholders cannot deduct any loss of the corporation.

If you are a C corporation, use the information in the chart below to help you determine some of the forms you may be required to file.

Corporations that are required to file 10 or more returns in a calendar year (calculated by aggregating all returns of any type) are required to e-file their Forms 1120 and 1120-S, effective for returns required to be filed on or after January 1, 2024. Find details on the final e-file regulations. For more e-file information, see e-file for Business and Self-Employed Taxpayers.


If you are a C corporation or an S corporation then you may be liable for... Use Form... Separate Instructions...
Income tax 1120, U.S. Corporation Income Tax Return Instructions for Form 1120 U.S. Corporation Income Tax Return PDF
Employment taxes
  • Social Security and Medicare taxes and income tax withholding
  • Federal unemployment (FUTA) tax

941, Employer's Quarterly Federal Tax Return or

943, Employer's Annual Federal Tax Return for Agricultural Employees (for farm employees)

940, Employer's Annual Federal Unemployment (FUTA) Tax return

Instructions for Form 941 PDF


Instructions for Form 943 PDF

Instructions for Form 940 PDF

Excise taxes Refer to the Excise Tax webpage