If you missed the April fifteenth tax-filing deadline, it's still important for you file as soon as possible, even if you owe taxes and can't pay them at this time. If you're due a refund, you are at risk of losing it if you don't file the return within three years.
If you don't file a tax return, don't worry, the IRS will remember you. They'll send you a letter inviting you to please file your tax return. It seems they don't forget a thing. And if they owe you, then that's a good thing. On the other hand, if you owe them and can't pay right now, they will work with you in a very civil manner.
You can also file for an extension to file a tax return. Just file a Form 4868 - Application for Automatic Extension of Time to File. Don't forget, you have to file this before the tax-filing deadline of April fifteenth. They won't accept the application after that date. Once you've filed your extension, you have until October fifteenth to file your tax return. If you owe money and you did file the extension, then you won't have to worry about late filing fees.
If you are out of the country on the tax filing due date for your return, you are entitled to two extra months to file your return and pay the amount due without requesting an extension. outside of the country means you live outside of the United States and Puerto Rico and you work outside of the United States and Puerto Rico, or you are in the military or naval service outside the United States and Puerto Rico.
Some other special situations may come up that may make you want to file your tax return after the filing deadline. To claim the Earned Income Credit (EIC), you must file a tax return to get it.
If you are self-employed, your tax return must report self-employment income within three years of the initial tax-filing deadline in order for you to receive Social Security credits toward your retirement.
If you can't pay the full amount of the taxes owed, you should file and pay as much as you can to avoid additional penalties.