If not submitted to NVC along with the Affidavit of Support form, the petitioner will need to provide the visa applicant with evidence of his or her domicile. We fully understand the various steps of the immigrant visa application process, including the visa pre-processing that occurs at the National Visa Center.On Form I864, petitioners must prove that they have the ability to financially support the visa applicant(s) if necessary. This guide will explain how to prove domicile when filling out Form I-864 ("Affidavit of Support"). Consular processing support without the high price tag. If you want to sponsor someone for a family-based green card, you need to provide proof of a U.S. domicile in your Affidavit of Support (Form I-864). Typically, in order to claim US domicile, the Affidavit of Support sponsor must be residing in the United States.