Kline, ColoradoKline is an unincorporated community on the Southern [Ute Indian Reservation] in La Plata County, Colorado, United States. ZIP code 81326 serves Kline, but mail must be addressed to the community of Hesperus.HistoryThe Southern Ute Indian Reservation was created on November 9, 1878. The Kline, Colorado, post office operated from April 22, 1904, until March 31, 1953.