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. AFFIDAVIT OF: Plaintiff. Defendant.Line-by-line guidance for properly filling out USCIS's I-864 Affidavit of Support to sponsor an immigrating family member. Affidavit of Support: This is a statement of a sponsor's income, resources, and willingness to support an alien. The Affidavit of Support (USCIS form I-864) is your validation that you have enough income to provide support for the person you are sponsoring in Greensboro. The I-864, also known as the affidavit of support, is a "4-Part" form in the Green Card Process, whether Adjustment of Status or Consular Processing. The affidavit of support is a contract between the sponsor and the federal government. Pages three through five inquire into your monthly expenses. Pages three through five inquire into your monthly expenses. 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.