In this article, we'll explain how to prove US domicile as part of your Affidavit of Support so you can successfully sponsor a family member for a green card. Visa status must confer the ability to establish domicile in the United States in order to be classified as an instate student.Examples of acceptable evidence. Description. Residence in the U.S.. Lease agreement; Mortgage payments; Utility bills. 1. Complete the Domicile Affidavit. 2. A copy or picture of your driver's license or voter registration. Must show occupant's name and property address. In establishing domicile, the alien must not hold a visa that prohibits establishing domicile in the United States and this state. Typically, in order to claim US domicile, the Affidavit of Support sponsor must be residing in the United States. How Can I Prove U.S. Domicile?