Concise Takeaway
Most individual tax returns are due April 15, with automatic extensions available. Special deadline rules apply to combat zone service members and taxpayers living abroad.
Standard Filing Deadlines
The income tax return is due on the 15th day of the 4th month after the end of the tax year.
For calendar‑year taxpayers, this is usually April 15.
If the due date falls on:
- A Saturday
- A Sunday
- A legal holiday
…the deadline moves to the next business day.
Timely Filing Rules
A return is considered filed on time if:
- A paper return is properly addressed, has sufficient postage, and is postmarked by the due date
- An e‑filed return is transmitted by an authorized provider on or before the due date
From the document: “A return sent using IRS e‑file is on time if the authorized electronic return transmitter postmarks the transmission by the due date.”
Automatic 6‑Month Extension
Taxpayers may request an automatic six‑month extension by:
- Filing Form 4868, or
- Paying all or part of the tax due electronically and designating the payment as an extension
This generally extends the filing deadline to October 15.
Taxpayers must estimate their tax liability when requesting the extension.
Combat Zone Extensions
Taxpayers serving in a combat zone or in a contingency operation receive extended filing and payment deadlines.
Extension Length
The deadline is extended:
- 180 days after the later of:
- The last day in the combat zone, or
- The last day of continuous hospitalization from combat‑related injury
- PLUS the number of days remaining in the normal filing period when the taxpayer entered the combat zone
This additional period represents the standard filing window (January 1–April 15).
Who Qualifies
- Armed Forces
- Uniformed services (including NOAA and Public Health Service officers)
- Support personnel such as Red Cross workers
From the document: “The deadline for filing and payment increases by 180 days… plus the number of days remaining to file upon entering the combat zone.”
Taxpayers Outside the United States
A U.S. citizen or resident receives an automatic two‑month extension to file and pay if, on the regular due date, they:
- Are on military or naval duty outside the U.S. and Puerto Rico, or
- Live and maintain a main place of business outside the U.S. and Puerto Rico
Interest still applies from the original due date.
A statement explaining the qualifying situation must be attached to the return.
Filing Deadline Flow Summary
- Determine standard due date
- Apply weekend/holiday rule
- If needed, request Form 4868 extension
- Apply special rules for combat zone service
- Apply two‑month extension for qualifying taxpayers abroad