The fiancé or fiancée of a U.S. citizen can qualify for a K-1 visa that allows him/her to immigrate to the United States.  The U.S. citizen spouse must submit a petition for a fiancé visa.  After the petition is approved, an application for a visa can be submitted at the nearest U.S. embassy or consulate.  Important note: the fiancé has six months after the visa is issued to travel to the United States, and the marriage has to occur within 90 days of arrival.