Filing your taxes late? Here's what you need to know

Tax season ends at midnight on Tuesday, April 15 - for most filers, at least.

Up to one in three Americans waits until the last minute to file their taxes, according to a 2021 survey by IPX 1031.

That amounts to tens of millions of people. And a portion of those late filers will grapple with the realization that they don't have enough time to submit their taxes by the end of Tax Day.

If you're one of them, here's what you should know and what you can do:

Last-minute taxpayers can file for an extension

A tax extension pushes back the filing deadline, affording taxpayers additional time to get their submission in order.

An extension, however, doesn't allow filers to delay payment. If you think you might owe the government money, then you must hand over the estimated amount by April 15. If not, you risk having to pay penalties and interest.

When estimating how much you owe, keep in mind changes to the tax code, such as updated tax brackets and new tax credits. Knowledge of those rules can help you optimize your tax refund.

Generally, the six-month extension is granted automatically, the IRS says, while also noting that the extension applies only to the time you have to file, not to the time you have to pay your estimated tax.

How do you file a tax extension?

Before filing an extension, check to see if you qualify for an automatic extension. That option is available to people who live in a federally declared disaster area, members of the military stationed abroad or in a combat zone, and citizens living outside the U.S.

First, if you opt to pay the anticipated amount of tax owed, you can check off an extension-request box in the IRS online payment portal.

Alternatively, you can submit an online extension request through the government's free service, IRS Free File.

Of course, you can always go about it the old-fashioned way by mailing the extension request. If you go that way, you should fill out the Form 4868 and send it to an address listed on the IRS website. The form requires filers to estimate the amount of tax owed for the filing year.

Lastly, you must submit your extension request by the end of the day on April 15.

Late tax filers could face penalties

If you file your taxes late and don't file for an extension first, you risk being hit with additional fees for the tardy submission. The penalty amounts to 5% of the taxes owed for each month that the filing is late, up to a maximum of 25%.

Under such circumstances, watch your mailbox for a notice from the IRS informing you of a late fee.

A tax extension lasts six months, meaning if you obtain one, you'll be allowed to submit your tax forms without penalty at any time up until Oct. 15.