Thermal is an unincorporated community within the Coachella Valley in Riverside County, California, United States, located approximately 25 miles southeast of Palm Springs and about 9.5 miles north of the Salton Sea. The community's elevation is 138 feet below mean sea level. It is served by area codes 760 and 442 and is in ZIP Code 92274. The population was 2,865 at the 2010 census.