Amarillo is a city in the U.S. state of Texas and the seat of Potter County. It is the 14th-most populous city in Texas and the largest city in the Texas Panhandle. A portion of the city extends into Randall County. The estimated population of Amarillo was 200,393 as of April 1, 2020. The Amarillo metropolitan area had an estimated population of 308,297 as of 2020.The city of Amarillo, originally named Oneida, is situated in the Llano Estacado region.