Sonoita is a census-designated place in Santa Cruz County, Arizona, United States. The population was 818 at the 2010 census.The origin of the name of the CDP is the O'odham Ṣon ʼOidag, which may be best translated as "spring field". Sonoita has for many years been a popular place for wealthy Arizonans to establish vacation and retirement homes and ranches. Sonoita is experiencing significant growth.