Can I get more time to file the tax returns?
There are three ways you can request an automatic extension of time to file a U.S. individual income tax return: (1) you can electronically file Form 4868 or Form 7004(PDF), Application For Automatic Extension of Time To File U.S. Individual Tax Return; (2) you can pay all or part of your estimate of income tax due using a credit or debit card or by using the Electronic Federal Tax Payment System (EFTPS); or (3) you can file a paper Form 4868 or 7004 by mail. If you file your Form 4868 or 7004 electronically you will receive an acknowledgement or confirmation number for your records and you do not need to mail in Form 4868 or 7004. If you need to pay additional taxes when filing Form 4868 or 7004 electronically, you may do so through the outside service provider or through e-file. You can refer to your tax software or tax professional for ways to file electronically using e-file services. Several companies offer free filing of Form 4868 or 7004 through the Free File program that you can access on the IRS.gov website. If you wish to file electronically, be sure to have a copy of last year's tax return. You will be asked to provide the adjusted gross income (AGI) from the return for taxpayer verification. A second way of requesting an automatic extension of time to file your individual income tax return is to pay part or your entire estimate of income tax due by credit card or debit card or by using EFTPS. You may pay by phone or Internet through one of the service providers listed on Form 4868 or 7004. Each service provider will charge a convenience fee based on the amount of the tax payment. At the completion of the transaction, you will receive a confirmation number for your records. Finally, you can request an automatic extension of time to file your individual income tax return by completing paper Form 4868 or 7004 and mailing it to the appropriate address provided on the form. Please be aware that an extension of time to file is NOT an extension of time to pay.
Extracted from the IRS at: http://www.irs.gov/taxtopics/tc304.html