Columbus is the capital and largest city of the U.S. state of Ohio. It is the 15th largest city in the United States, with a population of 850,106 (2015 estimate).

It is the core city of the Columbus, OH Metropolitan Statistical Area (MSA), which encompasses a ten county area.[18] It is Ohio's third largest metropolitan area, behind Cleveland and Cincinnati.

Under the Combined Statistical Area (CSA) model, the Columbus, OH Metropolitan Statistical Area was the 25th largest in the United States.

According to the U.S. Census Bureau, the Columbus-Marion-Zanesville, OH Combined Statistical Area (which also includes Marion, Chillicothe, and Mount Vernon) has a population of 2,424,831, making it the second largest metropolitan area in Ohio behind Cleveland.

 It is also the fourth most populous state capital in the United States, and the third largest city in the Midwestern United States.