If you don't send yoru return to the IRS by the April 15 deadline, you'll get hit with a failure-to-file penalty, which starts at 5% of however much you owe, maxing out at 25% of your tax bill. If you wait more than 60 days to file, you're charged a $135 fee or 100% of the taxes you owe (whichever is less).Mar 6, 2014
How far back can you file taxes?
The IRS prefers that you file all back tax returns for years you have not yet filed. That said, the IRS usually only requires you to file the last six years of tax returns to be considered in good standing. Even so, the IRS can go back more than six years in certain instances.