Filing Late

• The IRS continues to accept tax returns after the April 15 deadline, and you can even file returns for previous tax years that you haven't filed yet. If you put off filing taxes because you couldn't afford your tax bill, contact the IRS to arrange for a payment plan. If you owe less than $25,000 in taxes, fees and penalties, the IRS may work with you to develop a payment plan to help you avoid delinquency.
  
  

Owed a Refund

• If you just didn't get around to calculating your taxes and then discover that the IRS owes you a refund on your late taxes, you're in luck. Starting in 2010, the IRS stopped assessing penalties and fees for late filers. If your filing is late by more than 45 days, the IRS begins paying interest on the unpaid refund, even it's delayed because of a late filing. The window to claim refunds from late returns isn't infinite, however. The statute of limitations for claiming late returns is three years, so your procrastination may cost you any refund you may be owed.
  
  

File as Soon as Possible

• If you're not owed a refund, you should still file your return as soon as possible to avoid any penalties and fees associated with delayed payments. The IRS assesses a 5 percent late-filing fee for each calendar month your return is late up to 25 percent. Additionally, if your return is more than 60 days late, you'll face a fine equal to 100 percent of your return or $100, whichever is smaller. The IRS also assesses interest charges on overdue tax payments at the rate of the federal short-term rate plus 3 percent, up to 25 percent of your tax owed.
  
  

Delinquent Taxpayers

• If you fail to file your own return too long, the IRS will calculate your tax bill for you. These calculations frequently overlook many deductions and credits for which you may qualify if you file your own return and present you with a bill. If you ignore a tax bill, the IRS may place a tax lien on your property or garnish your wages until your tax bill is settled. If you miss the deadline and contact the IRS voluntarily to begin working out a repayment strategy, you'll avoid criminal charges in all but the most flagrant violations.