If you are petitioning (sponsoring) a foreign-born family member to immigrate to the United States, you probably know from Nolo's books or articles that you need to fill out an Affidavit of Support on Form I-864, issued by U.S. Citizenship and Immigration Services (USCIS), and to supply supporting documents along with it. The purpose of this form is to prove that you have the financial capacity to support the immigrant if he or she is unable to become self-supporting during the first years after arriving in the U.S., and that you formally agree to provide this support.
As part of proving your financial capacity, you must submit documentation of your income, including federal (not state) tax information for the last one to three years. The USCIS prefers to receive this in the form of tax transcripts, which are IRS-generated records of your tax filings. (Transcripts from the IRS are harder to forge than homemade copies of your past tax returns.)
In the past, requesting these tax transcripts could add many weeks to the process of preparing your Form I-864 submission. Now, however, the IRS has created an online system for downloading and printing your tax transcript immediately. Go to the "Get Transcript" page of the IRS website and follow the instructions to get a "tax return transcript."