Marriage Based Visas & K-1 Visa – The purpose of this form is to request the agency’s approval to allow your spouse to live in the U.S. as a permanent resident. It also provides you with the opportunity to prove that you have a valid marriage, which is the basis of any marriage-based petition. The fiancé(e) K-1 non-immigrant visa is for the foreign-citizen fiancé(e) of a U.S. citizen. The K-1 visa permits the foreign-citizen fiancé (e) to travel to the United States and marry his or her U.S. citizen sponsor within 90 days of arrival.