Filing Process

• To file for previous tax years, download the forms, instructions and schedules needed for your filing from the IRS website. Unlike current year tax returns, prior year returns cannot be filed using e-file software. This means that you're required to complete the returns by hand and mail them in separately to the IRS office which is responsible for processing returns for your region. If you are not sure which office processes returns for your region, consult the IRS website.
  
  

Income Information

• To complete your previous years' returns you'll need your previous years' income information. If you do not have your income information, complete IRS form 4506-T and mail it to the address listed in the instructions for the form. On form 4506-T, enter your name and address in the first section, check box 8 to indicate your request for wage information and in box 9 enter the years for which you are requesting the information. Sign and date the form and then mail it. There is no fee for requesting a wage statement and you should allow at least 10 days for receiving your transcripts in the mail.
  
  

Penalty and Interest

• If you owe tax as a result of your late filing, then you will be charged penalty and interest on the unpaid tax beginning from the date the return was due. The failure to file penalty is 5 percent of the unpaid tax for each month that it remains unpaid, and the failure to pay penalty is 1/2 of 1 percent for each month the tax remains unpaid. Interest also accumulates on the tax owed.
  
  

Statute of Limitations

• Although you can file your return at any time, you are only allowed three years from the due date of the return to file and receive a refund. After the three-year statute has expired, you forfeit your refund.
  
  

Warnings

• If you have more than one year of prior year returns to file, it is easy to get confused and file them all with the same tax rules in mind. This is especially true since you can't use an online software to check your entries. So be especially careful to consult a copy of Publication 17 for each year in which you're filing. Tax law changes every year. Deduction amounts, eligibility requirements, and standard deductions are continually adjusted and if you don't use the tax law specific to the year in which you file, you could make a mistake that ends up costing you money.