How to file an extension for taxes?

About tax deadlines and extensions

For the 2023 tax year, the federal tax filing deadline falls on Monday, April 15, 2024. Note, however, that Maine and Massachusetts residents have until April 17, 2024, to file their taxes due to the Patriots’ Day and Emancipation Day holidays. 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, provided it is 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 of these tax deadline exceptions vary widely based on your unique situation, so make sure to check with the IRS regarding your individual circumstances.

How to fill out Form 4868 for a tax extension

According to Castelan, you don't need to provide an explanation to the IRS when you file for a federal tax return extension. Instead, you need to have a copy of your prior year's return, and you'll provide the IRS with your personal information, your estimated total tax liability for 2023, the total 2023 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.

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Tax extension approval

Castelan said that after you submit Form 4868 for a federal tax return extension, you will 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 paying 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. For example, paying your estimated tax payment by the regular tax filing deadline of April 15 (April 17 in Maine and Massachusetts) can help you avoid a late filing 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.

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 Out-of-date information like old addresses or last names that don't match IRS records can also lead to a rejection of the form.

If your extension gets 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 required to request 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 when you need to file by.

Note that, 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 Wisconsin, Alabama and California, don't require you to request an extension to file late.

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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.