File Form 1040EZ by April 15, 2010. If you file after this date, you may have to pay interest and penalties. See What if You Cannot File on Time? on page 21 for information on how to get more time to file. There is also information about interest and penalties.
If you were serving in, or in support of, the U.S. Armed Forces in a designated combat zone or a contingency operation, you can file later. See Pub. 3 for details.