In most cases, the individual who filed the visa petition for the intending immigrant must be the sponsor in Form I-864, Affidavit of Support. But when a petitioning sponsor is unable to meet the income requirements, another individual must also sign a separate form as a joint sponsor to meet the financial requirements and to support the intending immigrant.
A joint sponsor on the I-864 Affidavit of Support does not have to be related to the intending immigrant or to the petitioning sponsor. At the same time, a joint sponsor must be a lawful permanent resident, a U.S. citizen, or U.S. national at the age of 18 or older, domiciled in the USA or its territories, and having an income of minimum 125% of the poverty level.
There may be 2 joint sponsors. In the case when the first joint sponsor can submit the form not for the whole family but only for a few family members, a second qualifying joint sponsor should be involved in order to support the remaining ones. Also, a joint sponsor must be able to satisfy the income requirements for all the individuals he/she is sponsoring without combining the resources with the second joint sponsor or with the petitioning sponsor.
Petitioning sponsor and joint sponsor(s) are legally accountable for the financial support of their sponsored immigrant(s).