Taxpayers have until midnight today to file their returns after a three-day grace period, granted because the federal government observed Washington D.C.'s Emancipation Day on Friday.
And as last-minute filers fill out their forms, another American tradition takes place: protesting taxes.
A group of tax watchers was planning a demonstration this afternoon in downtown Tampa to voice concerns about large corporations using loopholes to get out of paying the maximum amount.
The Make Them Pay protest was scheduled for 3:30 p.m. in front of the Bank of America tower, 101 E. Kennedy Blvd.
Organizer Chris Radulich said he hopes for 100 to 150 people to show up.
"There is quite a number of organizations and unions involved," he said.
"We can't stand the way the state is progressing, and the national government," he said. "This one is to point out the fact that while we individuals are paying taxes, corporations are using loopholes and even getting rebates."
Meanwhile, rank-and-file taxpayers who don't utilize online tax services are expected to hoof it to post offices to get their returns postmarked today.
Tampa's main post office at Tampa International Airport will remain open until midnight with workers stationed along the drive collecting returns. St. Petersburg's main post office will stay open until 7 p.m.
"We stopped getting the huge crush a few years ago" because of online filing, said Gary Sawtelle, spokesman for the U.S. Postal Service in Tampa. "It's a lot slower than it used to be. We're expecting a good right-after-work crowd, but after that, it tapers off."
The convenience for those mailing returns at the airport office is the drive-thru feature. Postal workers will collect returns from drivers and postmark them without the customers having to get out of their cars, Sawtelle said.
The trend away from paper returns means fewer people mailing at the last minute, he said.
"A few years ago, we opened up other post offices," around the Tampa Bay area, he said. "But now we don't need it. It's been very, very light the last couple of years."
IRS officials said about 6.4 million Floridians have already filed returns, with 2.4 million still missing.
Electronic filing is gaining popularity, up 7 percent from last year. Officials said that electronically filed returns made up 84 percent of the returns the IRS has received.
That percentage will drop, as a majority of those filing close to the deadline use paper forms, officials said.
Those who can't make the deadline can request an extension, but that request has to be sent by today. Filers who want more time need to send the IRS a Form 4868 by mail or electronically. Typically, the government grants a six-month grace period for taxpayers who properly file requests for extensions.
The IRS expected to get more than 10 million requests for extensions, tax experts said.
The IRS has penalties for failing to file or pay on time. Typically, the failure to file on time carries a heftier fine, so if taxpayers can't pay right way they still should get their forms filed. There are options available for payments after the tax returns are in.