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. If you have a joint sponsor, the joint sponsor must also complete and sign USCIS Form I-864.You, the sponsor (petitioner), and the joint sponsor must complete Form I-864. See tips for completing Form I-864. In this video we're going to show you how to complete an i 864 and affidavit of support that is needed as part of the package for an adjustment of status. The affidavit of support ensures that the intending immigrant will not become a financial burden to the U.S. government. Your sponsor must fill out the attached form. This video will help you to fill out I-864 For Joint Sponsor. You must also submit an affidavit of support for your parent, referred to as the I-864 form. 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.