Use this form to show they have adequate means of financial support and are not likely to rely on the US government for financial support. Completing and signing Form I-864 makes you the sponsor.864 Affidavit of support How to fill out the Form 864 immigration Tips US mmigration with Attorney Jacob Sapochnick The purpose of the Affidavit is to assist consular officers in determining whether a visa applicant will have adequate means of financial support in the US. The "Affidavit of Support" is a signed document to accept financial responsibility for a family member who is seeking a green card. Line-by-line guidance for properly filling out USCIS's I-864 Affidavit of Support to sponsor an immigrating family member. 864 Affidavit of support How to fill out the Form 864 immigration Tips. Your financial sponsor(s) or you will need to submit evidence of income in the form of bank statements, loan letter or scholarship letter. The ISS at Queens College assists students and faculty in obtaining and maintaining F-1 and J-1 immigration status on a short-term basis. Some sponsors temporarily reside abroad and intend to move to the US once a family member's immigrant visa is issued.