Form 4868 ยท Tax year 2026
Tax Extension: Time to File, Not Time to Pay
An extension of time to file moves one date and leaves the other standing. Request it by Thursday, April 15, 2027, and your tax year 2026 return is due on Friday, October 15, 2027 instead, six months later, with no filing penalty for those months. The tax itself is still due on April 15, 2027. Anything owed and left unpaid after that date draws interest, and the late payment penalty as well, extension or no extension. The request is made on Form 4868, it is automatic, and this page files nothing: it explains the form and links to the IRS pages that take the request.
Last reviewed: November 4, 2026.
The two dates, and what each one governs
| Request and payment deadline | Thursday, April 15, 2027. The extension request must be made by this date, and tax owed for 2026 is due by this date. |
|---|---|
| Extended filing deadline | Friday, October 15, 2027. The return itself is due by this date when the extension was requested on time. |
| Length of the extension | Six months, automatic. No reason is required and no approval is issued. |
| Weekend and holiday rule | The IRS rule is that a due date falling on a Saturday, Sunday, or legal holiday moves to the next day that is none of those. Neither 2027 date falls on a weekend or holiday, so neither date moves. |
What an extension does, and what it does not do
- It does move the deadline for filing the return. A return filed by October 15 under a timely extension is filed on time, and the late filing penalty, which the IRS figures at 5 percent of the unpaid tax per month in its own worked example, does not run for the extension months.
- It does not move the deadline for paying the tax. The IRS states the point at the top of its extension page: make sure you pay any tax you owe by the April filing date; the extension is only for filing your return.
- It does not stop interest. The IRS interest page states that underpayment interest applies even if you file an extension. Interest is charged on the unpaid amount starting on the due date of the amount owed and continues until the balance is paid in full, at a rate the IRS sets quarterly.
- It does not stop the late payment penalty. The IRS figures the failure to pay penalty at 0.5 percent of the unpaid taxes for each month or part of a month the tax remains unpaid, up to 25 percent of the unpaid taxes. An approved payment plan reduces that rate to 0.25 percent per month while the plan is in effect.
- It does not extend any other deadline. Quarterly estimated payments for the following year keep their own due dates, and state returns follow state rules, not the federal extension.
the tax is still due April 15
The three ways the IRS takes the request
- Pay online and check the box. Pay what you owe through an IRS online payment option and indicate that the payment is made as part of filing for an extension. The IRS states that no separate extension form is then required, and that you receive a confirmation number for your records.
- File Form 4868 electronically. The form can be e-filed through tax software or a tax professional. The IRS also states that IRS Free File can be used to electronically request an automatic extension, and that no income limit applies to extension requests made that way. The IRS Free File page explains that route.
- File Form 4868 by mail. The paper form goes to the IRS address the form's instructions assign to your state, with any payment made by check or money order.
Whichever route is used, the form asks for the same estimate: the tax you figure for the year, less the tax you have already paid through withholding, estimated payments, and credits, leaving the balance owed. The estimate is made from the records available in April. It is not the return, and a balance that turns out larger is settled on the return itself, with interest on the unpaid part running from April 15.
Special positions the IRS publishes
- Living outside the United States. A United States citizen or resident alien who, on the regular due date of the return, is living outside the country receives an automatic two month extension, to June 15, 2027, without requesting it, and can request the further extension to October 15 on Form 4868. Interest still runs on tax unpaid after April 15.
- Disaster areas. The IRS grants added time, for filing and in stated cases for payment, to taxpayers in areas it names after a federally declared disaster. The relief is published area by area on irs.gov; this page does not track it.
- A balance that cannot be paid. The IRS's published route is to file on time or on extension, pay what you can by the due date, and apply for a payment plan for the rest. Interest continues on the unpaid balance under a plan, as it does everywhere else; the late payment penalty rate is lower while an approved plan is in effect.
An extension year is also the year the estimated payments most often go wrong, because the return that would have settled the figures is the one being postponed. The quarterly estimated tax calculator works through the four payment dates and the safe harbour rules that govern those payments.
Questions and answers
Do I have to give a reason, or wait for the IRS to approve the extension?
No. The extension is automatic. Form 4868 is titled an application for automatic extension of time to file, and the IRS grants the six months when the request is made properly and on time, by the April filing deadline. There is no reason to state and no approval to wait for. What the request must carry is an estimate of the tax for the year, figured from the information available, less the tax already paid through withholding and estimated payments.
I cannot pay anything by April 15. Should I still request the extension?
Yes. The two penalties are separate, and the one the extension stops is the larger one. The IRS figures the late payment penalty at 0.5 percent of the unpaid tax for each month or part of a month, and its own worked example puts the late filing penalty at 5 percent for the month, ten times the rate. An extension moves the filing deadline to October 15, so the filing penalty does not run during those months. Interest runs either way, from April 15 until the balance is paid. The IRS's advice for a balance that cannot be paid in full is to pay what you can by the due date and apply for a payment plan, which also reduces the late payment penalty rate to 0.25 percent per month while the plan is approved and in effect.
Does an extension change my quarterly estimated payments?
No. The extension covers the filing of the return for the year just ended. Estimated payments for the current year keep their own four due dates, and an unpaid balance for the earlier year is not cured by paying the new year's estimates. The quarterly estimated tax calculator page works through those dates and the safe harbour rules for the payments themselves.
Does the federal extension cover my state return?
States set their own rules. Some states accept the federal extension for their return, some require their own form, and some take an extension for filing while still expecting payment by their own date. Nothing on this page states a state rule; check your state tax agency's published position before relying on the federal extension for a state return.
Sources
- IRS, Get an Extension to File Your Tax Return, irs.gov. States that an extension request by the April filing due date gives until October 15 to file without penalties; that any tax owed must be paid by the April filing date because the extension is only for filing the return; the three routes (pay online and check the box, with a confirmation number and no separate form; IRS Free File, with no income limit for extensions; Form 4868 by mail, filed online with an e-file partner, or through a tax professional); that the form carries an estimate of tax owed less taxes already paid; the automatic two month extension for citizens and resident aliens living outside the United States on the due date; and added time for taxpayers affected by a disaster situation. Retrieved November 4, 2026.
- IRS, Failure to Pay Penalty, irs.gov. States that the failure to pay penalty is 0.5 percent of the unpaid taxes for each month or part of a month the tax remains unpaid, not exceeding 25 percent of the unpaid taxes; that it is reduced to 0.25 percent per month during an approved payment plan following a timely filed return; and, in its worked example of both penalties applying in one month, that the failure to file penalty runs at 5 percent for the month before the reduction. Retrieved November 4, 2026.
- IRS, Interest, irs.gov. States that the IRS charges underpayment interest when tax is not paid by the due date; that the underpayment interest applies even if you file an extension; that interest on tax starts on the due date of the amount owed, because extensions to file do not extend the date for payment of the tax, and continues to accrue until the balance is paid in full; and that underpayment interest rates vary and may change quarterly. Retrieved November 4, 2026.
Last reviewed: November 4, 2026.