The Internal Revenue Service reminded taxpayers that they have two weeks remaining until the April 18 filing deadline and that they can use IRS Free File to do their taxes or file an extension.

As of March 25, the IRS has received more than 82 million individual income tax returns, which is 58 percent of the 141 million returns expected this year. The IRS has received about the same number of returns so far this year as it did at this time last year, while processing of returns is up 3 percent from the same time last year.

Numerous economic recovery tax credits are also still available. The IRS reminded taxpayers that for some credits, such as the Making Work Pay Credit, individuals must claim the $400 ($800 for married couples) in order to receive it. (Use Schedule M to calculate your Making Work Pay credit.)

Usually, 20 to 25 percent of all taxpayers file in the final two weeks of the tax season. And, usually, about 7 percent of taxpayers seek a six-month extension to file.

Taxpayers have an extra weekend to file this year because of a District of Columbia holiday. The deadline for 2011 is Monday April 18, instead of April 15.

The IRS offered these filing tips as the final countdown begins:
. Start now to gather information and prepare your return to avoid hasty and possibly costly errors;

. Many tax credits from the American Recovery and Reinvestment Act (ARRA) are available. There's an expanded American Opportunity Credit of up to $2,500 for tuition, books and fees; a larger energy credit of up to $1,500 and an expanded Earned Income Tax Credit for larger families of up to $5,666. The $8,000 first-time homebuyer credit is still available for people who entered into a binding contract by April 30, 2010, and went to settlement by September 30, 2010;

. Consider using IRS Free File, which is brand-name software or online fillable forms, to prepare and e-file your returns - at no charge. Software is available to the 70 percent of taxpayers - those who earn $58,000 or less. And, fillable forms have no income limitations. Get started at www.irs.gov/freefile;

. File electronically to get a faster refund, have secure, encrypted transmission and a more accurate tax return. You can e-file through your tax preparer, through commercial software or through IRS Free File;

. If you cannot meet the April 18 deadline, file an extension, Form 4868, Application for Automatic Extension of Time to File U.S. Individual Income Tax Return. All taxpayers can use Free File to submit a Form 4868 for an automatic six-month extension. And, Free File will be available through the October 17 extension deadline for late filers.

. The six-month extension is to file a return only; it is not an extension to pay taxes due. If you are unable to pay your taxes, file a tax return anyway to lessen the penalties and pay all that you can. Then work with the IRS to set up a payment plan or you can go to IRS.gov and use the Online Payment Agreement Application.

In addition to Free File, the IRS offers other free tax help services through volunteers at 12,000 sites nationwide. The Volunteer Income Tax Assistance (VITA) sites serve taxpayers whose 2010 incomes were $49,000 or less. Tax Counseling for the Elderly sites serve taxpayers who are 60 and older. A list of sites is available on IRS.gov.