An affidavit of support is a document that someone signs to accept the financial responsibility of another person, says the United States Department of Homeland Security. The person who signs the document, called the sponsor, is usually accepting responsibility for a relative coming to the United States to permanently reside.
An affidavit of support is legally enforceable, and the responsibility of the sponsor usually lasts until the family member is credited with 40 quarters of work or becomes a U.S. citizen, explains the U.S. Department of Homeland Security.
People who file an immigrant visa petition for their relatives must be the sponsors. They must be at least 18 years old and U.S. citizens or permanent residents, having domiciled in the United States or a territory or possession of the United States. If the person lives abroad, he can still be a sponsor if he can show his residence abroad is temporary, and that his main domicile is in America, says the U.S. Department of Homeland Security.
The sponsor should complete the affidavit of support when his relative has been scheduled for an immigrant visa application to be adjusted to permanent resident status with the U.S. Immigration Department or with an Immigration Court in the United States, reports the U.S. Department of Homeland Security.