Tax reference

Deadlines and reference notes for U.S. business tax cycles.

Reference only. Deadlines that fall on weekends or federal holidays typically shift to the next business day. State and local deadlines vary. Confirm with a licensed tax professional for your specific situation.

Key federal dates (calendar-year filers)

Date	Deadline	Applies to
January 31	1099-NEC / W-2 recipient copies	Contractor and employee copies distributed.
March 1	Delaware Franchise Tax + Annual Report	Domestic Delaware corporations.
March 15	Form 1120-S / Form 1065	S-corporations and partnerships (calendar year).
April 15	Form 1120 / Form 1040	C-corporations and individuals (calendar year).
April 15 · June 15 · Sept 15 · Jan 15	Estimated tax payments	Quarterly estimated payments for calendar-year filers.
Sept 15 / Oct 15	Extended business & individual returns	Extended deadlines for filers on extension.

Nothing on this page constitutes tax advice. Coordinate specific filings with a licensed tax professional.