Rancho Santa Margarita is an affluent city in Orange County, California. One of Orange County’s youngest cities, Rancho Santa Margarita is a master planned community set upon rolling hills. The population was 47,853 at the 2010 census, up from 47,214 at the 2000 census.
Although it is named for Rancho Santa Margarita y Las Flores, which was in San Diego County, the city limits fall within the borders of Rancho Mission Viejo.
According to the 2010 United States Census, Rancho Santa Margarita had a median household income of $102,975, with 3.9% of the population living below the federal poverty line.