Saipan is the largest and most populous island in the Northern Mariana Islands (NMI), which is a U.S. Commonwealth in the western Pacific Ocean. Saipan serves as both the capital and the largest city of the Northern Mariana Islands. According to 2020 estimates by the United States Census Bureau, the population of Saipan was 43,385, a decline of 10% from its 2010 count of 48,220.