How the dates are set
Individual returns are due on the fifteenth day of the fourth month after the year ends: April 15 (IRC 6072). Partnership and S corporation returns are due on the fifteenth day of the third month: March 15. An automatic six-month extension (IRC 6081, Form 4868 for individuals) moves the filing date to October 15. Estimated tax is paid in four installments due April 15, June 15, September 15 and January 15 of the following year (IRC 6654). When any of these lands on a Saturday, Sunday or a legal holiday, the act is timely if done on the next business day (IRC 7503). Legal holidays are the federal holidays, plus, for returns filed with the IRS, holidays observed in the District of Columbia, which is how Emancipation Day (April 16) has pushed the April deadline in several past years.
The 2027 calendar
| Date | Day | What is due | Shift? |
|---|---|---|---|
| January 15, 2027 | Friday | Fourth estimated-tax payment for 2026 (Form 1040-ES) | None |
| February 1, 2027 | Monday | Employers furnish and file Forms W-2 and 1099-NEC | January 31 is a Sunday |
| March 15, 2027 | Monday | Partnership (Form 1065) and S corporation (Form 1120-S) returns; Form 7004 for a six-month extension | None |
| April 15, 2027 | Thursday | Individual returns (Form 1040) and payment; C corporation returns (Form 1120, calendar year); first 2027 estimated payment; last day for 2026 IRA and HSA contributions; Form 4868 extension request | None: Emancipation Day is Friday the 16th |
| June 15, 2027 | Tuesday | Second estimated payment; automatic two-month deadline for citizens living abroad | None |
| September 15, 2027 | Wednesday | Third estimated payment; extended partnership and S corporation returns | None |
| October 15, 2027 | Friday | Extended individual and C corporation returns | None |
| January 18, 2028 | Tuesday | Fourth estimated payment for 2027 | January 15 is a Saturday and Monday the 17th is Martin Luther King Jr. Day |
Add these dates to your calendar. The file opens in Apple Calendar and Outlook and imports into Google Calendar. It holds the six dates that apply to individuals, each with a reminder a week ahead.
The one date that moves twice is the last one: January 15, 2028 falls on a Saturday, the following Monday is a federal holiday, so the fourth 2027 installment is due Tuesday, January 18, 2028. Our estimated tax calculator prints the same shifted dates.
April 15 is only the filing date
Three separate things are due April 15. The return itself can be extended to October 15 by filing Form 4868, or by paying part of the tax electronically and marking it as an extension payment. The payment cannot be extended: tax unpaid after April 15 accrues the failure-to-pay penalty and daily interest from that day regardless of the extension. And the first estimated payment for 2027 is due the same day, which surprises people who owed for 2026 and did not adjust their withholding. The extension guide covers the mechanics; the late-filing calculator shows what missing the date costs.
Contribution and election deadlines that ride on April 15
A traditional or Roth IRA contribution for 2026 can be made until April 15, 2027, not October, even with an extension. The same is true of an HSA contribution for 2026. A SEP-IRA or Solo 401(k) employer contribution, by contrast, can be made until the extended due date of the business return. Designate the year when you contribute; custodians default to the current year in January and February.
Employer and business dates
Employers face January 31 (February 1 in 2027) for Forms W-2 and W-3 to the Social Security Administration and for Form 1099-NEC to the IRS; the other 1099 forms, filed electronically, are due March 31. Quarterly Form 941 is due the last day of the month after each quarter: April 30, July 31 (a Saturday in 2027, so August 2), November 1 (October 31 is a Sunday) and January 31, 2028 (a Monday). Federal tax deposits follow their own monthly or semiweekly schedules, covered on the deposit-penalty calculator.
Disaster postponements
After a federally declared disaster the IRS postpones filing and payment deadlines for taxpayers in the affected counties, sometimes by months. The postponement applies only where the IRS notice says it does and only to the periods it names; a state emergency declaration alone does not move a federal date. Check the IRS disaster relief page for your county before assuming a later date.
Key takeaways
- Individual returns and payment: Thursday, April 15, 2027; extension to October 15, 2027.
- Estimated payments: January 15 and April 15, June 15, September 15, 2027, then January 18, 2028.
- W-2s and 1099-NECs: February 1, 2027. Partnerships and S corporations: March 15, 2027.
- IRA and HSA contributions for 2026: April 15, 2027, extension or not.
- A date on a weekend or legal holiday moves to the next business day; apart from that, only an IRS disaster postponement moves it.
Sources
- 26 U.S.C. 6072: Time for filing income tax returns (15th day of the fourth / third month): prelim
- 26 U.S.C. 6654(c): Estimated tax installment due dates: prelim
- 26 U.S.C. 7503: Time for performance of acts where last day falls on Saturday, Sunday, or legal holiday: prelim
- IRS: When to file: 22-May-2026
- U.S. Office of Personnel Management: Federal holidays 2027 and 2028: page read 3 Sep 2026