Form I134 is used to document the personal finances of a sponsor who lives in the United States. This tip sheet will help you complete Form I864, Affidavit of Support Under Section 864A of the INA.Detailed Instructions for Affidavit. The "Affidavit of Support" is a signed document to accept financial responsibility for a family member who is seeking a green card. 864 Affidavit of support How to fill out the Form 864 immigration Tips. Some sponsors temporarily reside abroad and intend to move to the US once a family member's immigrant visa is issued. Many people have questions or doubts about how exactly to fill out the I134, Affidavit of Support form for a US tourist visa. Form I864, Affidavit of Support, needs to be filed DHS if you are a U.S. citizen or LPR planning to sponsor a spouse or family member. Note: Mistakes in completing the I-864 are a common reason for delays with an immigrant visa application. A copy of the Affidavit of Support form .