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How Filing Tax Extensions Works

        Money | Taxes

Paperwork Needed for Filing Tax Extensions
In 2006, the federal income tax filing deadline was April 17. The customary April 15 deadline happened to be on a Saturday, and federal law prohibits tax filing and payment deadlines from falling on weekends.
In 2006, the federal income tax filing deadline was April 17. The customary April 15 deadline happened to be on a Saturday, and federal law prohibits tax filing and payment deadlines from falling on weekends.
Justin Sullivan/Getty Images

Some people in the United States file their federal income tax returns before April 15 -- sometimes long before. Others file their returns at 11:50 p.m. on April 15.

But you may need even more time. If you haven't received all of your 1099 or W-2 forms -- records of how much income you have received from various sources -- you may not have all the numbers you need to fill out your 1040. Or maybe you don't have the numbers from your 1098 interest forms. Or maybe your tax return is just enormously complicated and you haven't had time to work on it.

Whatever the case, the worst thing you can do is to not file for an extension. Fortunately, it's really very simple: Fill out IRS Form 4868 and mail it in by April 15.

Filling out Form 4868, available on the IRS website, can give you an extra six months to file most federal income tax forms, including the 1040, 1040A, 1040EZ, 1040NR and 1040NR-EZ. If the IRS grants you an extension, your new filing deadline becomes October 15.

Form 4868 is simple, a mere nine lines long. You'll need to provide:

  • contact information, including your Social Security number (and your spouse's, if applicable)
  • your estimated tax liability -- that is, what you think you will owe
  • the amount you can pay now

You can file Form 4868 by mail, over the Internet, via tax software or even by telephone.

The IRS highly recommends making a payment on your estimated tax liability when you file Form 4868, because a filing extension is not a payment extension. Any tax you owe begins to accrue late payment penalties and interest after April 15. If you can't pay all of it, you have the option of paying whatever you can manage at the time. Every little bit helps reduce penalties and interest.

If you don't have enough money in your bank account to pay the estimated tax, you have the option of paying taxes by credit card. Of course, whether this is wise depends on your financial situation and your credit card's interest rate.

Oops. You didn't file on time, and you didn't file for an extension. What will the IRS do to you? Read on.