Hazelton is a city in Jerome County, Idaho, United States. The population was 807 at the 2020 census. It is part of the Twin Falls, Idaho Microp…Hazelton is a city in Jerome County, Idaho, United States. The population was 807 at the 2020 census. It is part of the Twin Falls, Idaho Micropolitan Statistical Area. According to the United States Census Bureau, the city has a total area of 0.38 square miles, of which, 0.37 square miles is land and 0.01 square miles is water.