The Twin Falls metropolitan statistical area (MSA), as defined by the United States Census Bureau, is an area consisting of two counties in the Magic Valley region of Idaho, anchored by the city of Twin Falls.

Twin Falls County is a county in the south central part of the U.S. state of Idaho. As of the 2020 census, the population was 90,046, making it the fifth-most populous county in Idaho. The county seat and largest city is Twin Falls. Twin Falls County is part of the Twin Falls, ID Twin Falls Metropolitan Statistical Area.