Filing a tax return does not extend your time to pay any tax you owe to the IRS. An extension of time to file, such as the automatic 6-month extension granted by filing Form 4868, only delays the deadline for submitting your return. It does not delay the deadline for paying any tax due. If you do not pay your tax by the original due date of your return (typically April 15 for calendar-year taxpayers), you will owe interest on the unpaid amount from that date onward. You may also be subject to penalties for late payment unless you have a valid reason, such as reasonable cause, for not paying on time.
Key Points:
- Extensions to file ≠ Extensions to pay: The IRS explicitly states that an extension to file does not extend the time to pay. This applies to both resident and nonresident aliens, as well as U.S. citizens abroad.
- Interest accrues from original due date: Interest is charged on any unpaid tax from the original due date of your return, regardless of whether you file an extension.
- Penalties may apply: Late payment penalties may be assessed unless you can demonstrate reasonable cause for not paying by the original due date.
- Combat zone and military service exceptions: If you are serving in a combat zone or are a member of the Armed Forces, you may qualify for special extensions that include both filing and payment deadlines. For example, members of the Armed Forces may defer payment of income tax for up to 180 days after release from service if their ability to pay is materially affected by military service.
Source:
Publication 519 (2025)
Publication 17 (2025)
Publication 3 (2025)
Disclaimer: Always verify details with the current year’s IRS forms, instructions, and publications, or consult a tax professional for personalized advice.