A K-1 fiancé visa is a nonimmigrant visa that allows a foreign fiancé to enter the United States with the purpose of getting married to a U.S. citizen. An approved visa will last for six months after it gets assigned. The couple has a time frame of 90 days from the entry date to perform the wedding and apply for Adjustment of status process, which will give the fiancé a legal permanent residence in the U.S.
The K1 nonimmigrant visa allows a foreign fiancé to enter the United States and get married within the next 90 days with the U.S. citizen who sponsors their petition. If the couple plans to live in the United States after getting married, the foreign spouse will have to apply for adjustment of status to get a permanent residence. The K1 visa is just temporary. By all means, it is not obligatory to stay within the United States permanently after getting married, so if there is no intention to stay, the foreign fiancé can enter the United States based on a tourist visa instead.
