Guilford County is a county located in the U.S. state of North Carolina. As of the 2020 census, the population was 541,299, making it the third-most populous county in North Carolina. The county seat and largest community is Greensboro. Since 1938, an additional county court has been located in High Point. The county was formed in 1771. Guilford County is included in the Greensboro-High Point, NC Metropolitan Statistical Area, which is also included in the Greensboro–Winston-Salem–High Point, NC Combined Statistical Area.

Greensboro is a city in and the county seat of Guilford County, North Carolina, United States. At the 2020 census, its population was 299,035; it was estimated to be 301,115 in 2022. It is the third-most populous city in North Carolina after Charlotte and Raleigh and the 69th-most populous city in the United States. The population of the Greensboro-High Point, NC Metropolitan Statistical Area was estimated to be 789,842 in 2023. The Piedmont Triad region, of which Greensboro is the most populous city, had an estimated population of 1,736,099 in 2023.