What is Form 1120-S?

Information about Form 1120-S, U.S. Income Tax Return for an S Corporation, including recent updates, related forms, and instructions on how to file. Form 1120-S is used by corporations that elect to be S corporations to report income, deductions, gains, losses, etc.

When is Form 1120-S due?

Form 1120-S requires you to report the income, gains, losses, deductions, and credits of your S corporation in addition to the distributions and allocations the corporation made to shareholders for tax purposes. Form 1120-S is due by the 15th day of the 3rd month following the end of the corporation’s tax year.

Who is liable for taxes on Form 1120-S?

The corporation is liable for taxes on lines 23a, 23b, and 23c on page 1 of Form 1120-S. Shareholders are liable for tax on their shares of the corporation's income (reduced by any taxes paid by the corporation on income). Shareholders must include their share of the income on their tax return whether or not it is distributed to them.