How to File an Extension for Taxes

About tax deadlines and extensions

For the 2025 tax year, the federal tax filing deadline falls on Wednesday, April 15, 2026. Those who want to file an extension for their tax return must do so by this date. At that point, the new tax filing deadline moves to Oct. 15.

There are a few ways to file for a tax return extension, including through IRS Free File. Tax professional Sonia Castelan of Castelan Tax Services pointed out that this is a public-private partnership between the IRS and several tax preparation and filing software companies and that it's free to use.

You can request an extension on your federal tax return by filling out Form 4868, Application for Automatic Extension of Time to File U.S. Individual Income Tax Return with the IRS. This can be done online right away, but it can also be submitted through the mail, as long as it’s postmarked by the tax filing deadline.

Tax deadline exceptions

A few special rules apply when it comes to tax filing deadlines, according to the IRS. If any of the following apply, you may have more time to file:

• You are serving in a combat zone or a qualified hazardous duty area.
• You are living outside the United States.
• You qualify for tax relief in disaster situations.

The rules regarding each tax deadline exception vary widely based on your unique situation, so make sure to check with the IRS regarding your individual circumstances.

Eligibility criteria for filing a tax extension

In general, you don’t necessarily have to meet strict criteria to request an extension for filing your federal taxes. If you meet the tax deadline exceptions we listed above or there’s another reason you need an extension to get all your paperwork together and file your taxes, fill out IRS form 4868 to request an extension.

According to Castelan, you don't need to provide an explanation to the IRS when you file for a federal tax return extension.

However, the extension to file is not an extension to pay. If you owe taxes, you’ll need to pay them by the April 15 deadline to avoid tacking on interest or penalties, even if the IRS grants your extension to file.

How to fill out Form 4868 for a tax extension

While you don't need to provide an explanation to the IRS when you file for a federal tax return extension, you do need to have a copy of your prior year's tax return.

You'll provide the IRS with your personal information, your estimated total tax liability for tax year 2025, the total 2025 tax payments you’ve already made and the amount you are paying when submitting the extension form.

Personal information required on the form includes:

• Your full name
• Address
• Social Security number (SSN)
• Spouse's SSN (if applicable)

You can file this form online through IRS Free File. You can also mail it to the IRS using the address listed under "Where to File a Paper Form 4868" on the form itself.

» COMPARE: Best tax software and services

Tax extension approval and next steps

Castelan said that after you submit Form 4868 for a federal tax return extension, you’ll receive an electronic acknowledgment that the IRS has accepted your filing. You should also plan to pay any amount due by the traditional tax filing due date to avoid interest and penalties for paying late.

Even if you can’t pay the full amount you owe immediately, Castelan recommends that you pay as much as possible to avoid penalties and interest that are based on how much you owe and how long you need to catch up on payments. Paying your estimated tax payment by the regular tax filing deadline of April 15 can help you avoid a failure to file penalty of 5% per month and a failure-to-pay penalty of 0.5% per month.

Castelan also noted that the maximum amount of penalties you can be charged for late taxes equals 25% of the unpaid tax amount. If you already know you cannot afford to pay the IRS the amount you owe this year, you should inquire about setting up an IRS payment plan right away.

Tax extension request rejection

Common reasons Form 4868 can be rejected by the IRS include name misspellings and incorrect SSNs and birthdates, according to Castelan. Out-of-date information such as old addresses or last names that don't match IRS records can also lead to a rejection of the form.

If your extension request is rejected before the due date, you will be notified via email or a letter from the IRS. At that point, you have five calendar days to correct and resubmit an extension for electronic retransmission to be still considered timely filed by the IRS.

Castelan said this is called the “Perfection Period,” per IRS Publication 4164. "If you cannot submit an extension electronically, the alternative is to paper-file Form 4868 and mail it by the tax due date to avoid potential penalties," she said.

How to request a state tax extension

While the process for requesting a federal tax return extension is standard no matter where you live, each state has its own requirements to request a state tax extension. This means you'll have to check with your state to find out which forms you need to file, if any, and the deadline for filing them.

As with federal taxes, you'll still have to estimate and pay amounts you owe your state by the traditional tax filing date when filing an extension to avoid penalties and other charges. Some states, such as Alabama, California and Wisconsin, don't require you to request an extension to file late.

» MORE: Pros and cons of IRS payment plans

Bottom line

According to Castelan, the most common reasons people file an extension include instances in which they are struggling to locate or organize essential tax records or are dealing with unexpected life events.

Fortunately, filing an extension for federal tax returns can give you tax relief in the form of an additional six months to round up the required paperwork and get your tax return to the finish line.

However, Castelan said she cannot emphasize enough that an extension doesn't give you more time to pay your taxes owed. "You should pay any amount due by the regular due date to avoid interest and penalty for paying late," she explained.