Due to tax law changes made by Congress under the American Taxpayer Relief Act on Jan. 2, the Internal Revenue Service will not begin processing individual income tax returns this year until Jan. 30.

That means if you're a person who is used to filing early to try to get a jump on an early refund, you'll have to wait.

"We have worked hard to open tax season as soon as possible," IRS Acting Commissioner Steven T. Miller said. "This date ensures we have the time we need to update and test our processing systems."

Most tax filers -- more than 120 million households -- can begin filing tax returns starting Jan. 30. Last year, the IRS began accepting tax returns that had been e-filed or Free-Filed on Jan. 17.

The IRS will be working closely with the tax software industry and tax professional community to minimize delays and ensure as smooth a tax season as possible, the agency said.

"Those people that would typically file electronically usually have a date of January 12th through the 15th to start filing returns," said Mike Isenhart of Isenhart Tax and Financial Services in Belleville. "Some individuals will think, well, hey, I'm going to go ahead and file on paper and get it in now and it will be in before the 30th, but the IRS has said they will hold those paper filings and won't process them until the 30th."

There is no advantage to filing on paper before the opening date, and taxpayers will receive their tax refunds much faster by using e-file with direct deposit, according to the IRS.

"The best option for taxpayers is to file electronically," Miller said.

More than 80 percent of taxpayers filed electronically last year, according to the IRS.

Although the IRS won't begin accepting filings until the 30th, taxpayers shouldn't wait until that date to start getting the paperwork ready to file.

"I can envision that there will be a lot of people at that point in time who file and there will be a glut of early filers," Isenhart said. "I expect the repercussions of that will carry on throughout the season. It is going to throw off the balance of things."

The later filing date could cause expected tax refunds to arrive later, but, the IRS expects refunds to be issued within normal timeframes. Most e-filed refunds were issued in fewer than 21 days last tax season.

"The IRS has been getting better at getting refunds out quicker, but with everybody waiting until the 30th (to file), it will be interesting to see how that affects things," Isenhart said.

The IRS estimated that some taxpayers won't be able to file until late February or March because of the need for more extensive forms and processing systems changes. A specific date has not yet been announced for this group of filers, which includes people claiming residential energy credits, depreciation of property or general business credits.

Most of those in this group file more complex tax returns and typically file closer to the April 15 deadline or obtain an extension.

Updated information will be posted on IRS.gov.