A K-1, or “fiancé visa,” is a temporary visa available only to fiancés of U.S. citizens who are living outside of the United States and intend to get married within 90 days of arriving in the United States. A marriage green card is available to spouses of both U.S. citizens and U.S. green card holders, whether living in the United States or abroad, and ultimately provides permanent residence. More info about the pros and cons of visas for fiancés vs. spouses