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. 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.In this guide, we will explain who needs to complete Form I864, when to file it, and how to fill out Form I864 stepbystep. Individuals immigrating through most family-based, and some employment-based,1 visa petitions are required to submit an Affidavit of Support on. If you are coming to the United States on a temporary visa, you may need to prove financial support. A sponsor can file the I-134 form. This form is required in most familybased green card applications, including CR1 and IR1 spouse visas and some employmentbased green card applications. After the appropriate form with documentation is complete, the petitioner should send it to the National Visa Center. What does the NVC do with the I-864? The person completing and signing this affidavit is the sponsor.