• The tax extension deadline is Oct.15, but some taxpayers in federally declared disaster areas have more time to file.
• For disasters after April 15, there is no extension for payments, and penalties and interest have been accruing.
• If you still can't pay your taxes, you have a few options, tax professionals say.

The tax extension deadline has arrived and there are options if you still can't pay your balance, tax experts say.

About 19 million U.S. taxpayers filed for an extension by the April 15 tax deadline, which bumped the filing due date to Oct. 15. But taxpayers affected by natural disasters may have even more time, with new deadlines ranging between Nov. 1 and as late as May 1, 2025, depending on location.

However, for federally declared disasters after April 15, filers were not granted more time to pay their tax bill. Penalties and interest on unpaid balances started accruing after the April 15 deadline.

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Many taxpayers wrongly assume that a tax extension provides more time to pay, experts say.

"That's a surprise to a lot of people," said Josh Youngblood, an enrolled agent and owner of The Youngblood Group, a Dallas-based tax firm. 

If you missed the tax deadline, the late payment penalty is 0.5% of your unpaid balance per month or partial month, capped at 25%. You will also incur interest on unpaid taxes.

By comparison, the failure-to-file penalty is 5% of unpaid taxes per month or partial month, up to 25%.

You have 'various payment options'

The IRS has options if you can't pay your taxes, "but you have to be current on your filing requirement," said Tom O'Saben, an enrolled agent and director of tax content and government relations at the National Association of Tax Professionals.

After filing, there are "various payment options" online, and many filers will receive an immediate acceptance or rejection of payment plan requests without calling the IRS, according to the agency.

"If you owe less than $50,000, establishing a payment plan with the IRS is almost going to be automatic," O'Saben said.

IRS online payment plans, or "installment agreements," include:

• Short-term payment plan: This may be an option if you owe less than $100,000, including tax, penalties and interest. You have up to 180 days to pay in full.
• Long-term payment plan: This may be available if your balance is less than $50,000, including tax, penalties and interest. You must pay monthly, and you have up to 72 months to pay off the balance.

Although the late-payment penalty and interest will continue to accrue, an IRS payment plan could cut your late-payment fee in half while the agreement is in effect, according to the IRS.

One downside of IRS payment plans is future tax refunds could be used to offset your unpaid balance, O'Saben said.

'Don't ignore it because it won't go away'

If you have unpaid taxes, you can expect notices from the IRS, and communication with the agency is key, experts say.

"Don't ignore it because it won't go away," Youngblood said. "I've had clients come in, and they have a whole pile of unopened IRS letters." 

"The IRS is not as bad as they think," he added. "They actually want to work with people."