The First Step toward an Immigrant Visa: Filing a Petition
As the first step, a sponsoring relative must file a Petition for Alien Relative, Form I-130 with the Department of Homeland Security, U.S. Citizenship and Immigration Services (USCIS).
In certain circumstances, a U.S. citizen living abroad can file an immigrant visa petition outside the United States.
U.S. Sponsor Minimum Age Requirement
U.S. citizens must be age 21 or older to file petitions for siblings or parents. There is no minimum age for a sponsor to file petitions for all other categories of family based immigrant visas. However, a U.S. citizen or lawful permanent resident (LPR) must be at least 18 years of age and have a residence (domicile) in the U.S. before he or she can sign an Affidavit of Support, Form I-864 or I-864-EZ. This form is required for an immigrant visa for a spouse and other relatives of U.S. sponsors.
Is Residence in the U.S. Required for the U.S. Sponsor?
Yes. As a U.S. sponsor/petitioner, you must maintain your principal residence (also called domicile) in the U.S., which is where you plan to live for the foreseeable future. Living in the U.S. is required for a U.S. sponsor to file the Affidavit of Support, with few exceptions.