Certified Public Accountant · Licensed in KansasLicensed in Kansas10965 Granada Lane, Suite 103 · Overland Park, Kansas 66211
Greg Heidrick, CPA, PAOverland Park, Kansas
(913) 397-9995Client portal

Dates the calendar already knows.

Standing federal dates from IRS Form 1040-ES and Publication 509. If a date falls on a weekend or legal holiday, the IRS moves it to the next business day.

SourceIRS
Telephone(913) 397-9995
OfficeOverland Park, KS
A legal pad with an April 15 due date written on it.
April on the pad1040-ES
DateWhoWhat
September 15, 2026IndividualsThird 2026 estimated tax payment (Form 1040-ES).
September 15, 2026Partnerships and S corporationsExtended 2025 returns (Forms 1065 and 1120-S) if an extension was filed.
October 15, 2026IndividualsExtended 2025 Form 1040, if an extension was filed.
January 15, 2027IndividualsFourth 2026 estimated tax payment. Not required if the 2026 return is filed and paid by February 1, 2027.
January 31, 2027BusinessesFurnish Forms W-2, 1099-NEC and many other information returns to recipients.
March 15, 2027Partnerships and S corporations2026 Forms 1065 and 1120-S, or file an extension.
April 15, 2027Individuals2026 Form 1040 and first 2027 estimated tax payment.
April 15, 2027C corporations2026 Form 1120, calendar-year corporations.
June 15, 2027IndividualsSecond 2027 estimated tax payment.

Confirm against IRS Form 1040-ES and Publication 509 before you rely on a date.