Calliham is an unincorporated community in northeastern McMullen County, Texas, United States, along State Highway 72 between Three Rivers and Tilden. Its elevation is 226�feet, and it is located at 28�28?50?N 98�21?01?W? / ?28.48056�N 98.35028�W? / 28.48056; -98.35028. Although it is unincorporated, it has a post office with the ZIP code of 78007.The climate in this area is characterized by hot, humid summers and generally mild to cool winters. According to the K�ppen Climate Classification system, Calliham has a humid subtropical climate, abbreviated "Cfa" on climate maps.