Filing Deadline

What is a filing deadline?

A filing deadline is the date by which a tax return or other required document must be submitted to avoid penalties. Different returns have different deadlines. Individual returns are due April 15. Partnership and S corporation returns are due March 15. Extensions push filing deadlines back but do not extend payment deadlines. Missing deadlines triggers penalties and interest.

Key federal filing deadlines

Form 1040 individual returns: April 15, or October 15 with extension. Form 1065 partnerships and Form 1120S S corporations: March 15, or September 15 with extension. Form 1120 C corporations: April 15, or October 15 with extension. Quarterly payroll taxes: the last day of the month following each quarter end—annual W-2 and 1099 forms: January 31. Know your deadlines and calendar them.

When deadlines fall on weekends or holidays

If a deadline falls on a Saturday, Sunday, or legal holiday, it moves to the next business day. This occasionally creates extended deadlines, but do not rely on this buffer. Plan to file before the stated deadline. Last-minute filings risk missing the window due to technical issues, missing information, or simple miscalculation of the adjusted date.