March 15th:

Note: If your due date falls on a weekend or holiday, you typically have until the next business day to file. Please contact us with questions.

Corporations

Calendar-year corporations:
Due date of prior year income tax returns (Form 1120 or Form 1120-A) for calendar-year U.S. corporations or calendar-year foreign corporations with offices in the U.S.

Last date for filing application (Form 7004) by calendar-year corporations for automatic six-month extension to file prior year tax return.

Calendar-year corporations' prior year information return (Form 5471) with respect to foreign corporations.

Fiscal-year corporations: Fiscal-year U.S. corporations and foreign corporations with a U.S. office must file by the 15th day of the 3rd month following the close of the tax year. Note that prior year information return (Form 5471) with respect to foreign corporations must be filed with income tax return.

S-corporations: Due date of prior year tax returns for calendar-year S corporations (Form 1120S).

Withholding