Tax day extended to April 18

NEW YORK (CNNMoney) -- You get three extra days to file your taxes this year. They'll be due on Mon., April 18.

But it's not because of a previously announced processing delay that will prevent people who itemize their taxes from filing before mid- to late February, the IRS said Tuesday. Instead, the bonus days come thanks to Emancipation Day, a little-known Washington, D.C., holiday that celebrates the freeing of slaves in the district.

Emancipation Day falls on Sat., April 16, but it is observed in D.C. on Fri., April 15. That prompted the IRS to extend the tax filing deadline to April 18 this year. Under the tax code, filing deadlines can't fall on Saturdays, Sundays or holidays.

The last time an extension was granted for this reason was in 2007.

But don't expect a separate -- or longer -- extension to make up for the IRS's processing delay, said IRS spokesman Anthony Burke.

The delay -- caused by Congress waiting until late December to pass new tax policies -- means that the 50 million taxpayers who itemize their taxes on a Schedule A form can't file until February.

However, the IRS estimates that less than 9 million taxpayers will end up being impacted by the delay, based on historical filing patterns.

"It's a very small percentage of folks who will be affected," said Burke. "There's no real reason why they would need time beyond April 18 because these are the people who want to file early anyway, and who may not be able to file early due to events the IRS couldn't really have done anything about."

People who do need more time to file their taxes can submit Form 4868 for a six-month extension, Burke added.