In order to obtain immigration benefits available to a spouse, there must be a valid marriage between the parties. In most situations, a marriage is valid for immigration purpose if it is recognized by the law of the state where it occurs. However, a marriage that is legally valid may still be disregarded if it is found to be a sham marriage, entered into by the parties to obtain immigration benefits and without any intention to live together as husband and wife. The marriage must also be legally subsisting at the time that the immigration benefit is sought with an exception where the US citizen is deceased.
Either the US citizen must also provide an affidavit of support, guaranteeing the support the immigrant spouse for at least 10 years or until the beneficiary becomes a US citizen. In order to guarantee this support, the sponsor must meet the annual income requirement of 125% of the current federal poverty guidelines or show that he or he has enough assets to support the immigrant spouse. If the sponsor cannot meet this income requirement, then he or she may find other joint sponsors.