Encinitas, CA. Sponsored Topics. Encinitas is a coastal beach city in San Diego County, California. Located within Southern California, it is approximately 25 miles (40 km) north of San Diego in North County and about 95 miles (153 km) south of Los Angeles. As of the 2010 census, the city had a population of 59,518, up from 58,014 at the 2000 census.