Concho is an unincorporated community and census-designated place in Apache County, Arizona, United States. Concho is located on Arizona State Route 61, 14 miles west of St. Johns. Concho was the original site for the state capitol, due to its prosperous farming. As of the 2010 census, the Concho CDP had a population of 38.Concho has the ZIP code 85924. The United States Postal Service operates the Concho Post Office along Arizona State Route 61.