Obtaining past copies of your return from the IRS can be expensive and should be avoided if possible. There are two free options the IRS provides before you need to pay for an actual tax return that was filed this year or in a prior year.
Tax Return Transcript
The Tax Return Transcript is an abbreviated form of your tax return with all line items, forms and schedules. This will most likely meet your needs in obtaining past tax information. These transcripts are free and can be obtained through a phone call to 1-800-829-1040 or through the mail accompanied by an IRS form 4506T-EZ or 4506T. These forms are available at IRS.gov.
Tax Account Transcript
The Tax Account Transcript shows adjustments made to the return after it was filed which will be extremely important in obtaining the true tax that you paid. It also provides the basic data from your return so as to match the Tax Account Transcript with the Tax Return Transcript. You should request both transcripts when you call or mail the IRS.
If you still need a copy of the actual return, then you will need to pay $57. This request also takes more time to process, 60 days as apposed to 10 days. Complete the form 4506 and mail it to the local IRS center listed on the form. You can request 6 years of prior returns if needed.