Pueblo is a home rule municipality that is the county seat and the most populous municipality of Pueblo County, Colorado, United States. Th…Pueblo is a home rule municipality that is the county seat and the most populous municipality of Pueblo County, Colorado, United States. The city population was 111,876 at the 2020 United States Census, making Pueblo the ninth most populous city in Colorado. Pueblo is the principal city of the Pueblo, CO Metropolitan Statistical Area and a major city of the Front Range Urban Corridor.