History
The city seal has the brands of Rancho Mission Viejo and Rancho Santa Margarita y Las Flores on the border, with artwork containing Santiago Peak in the background. The tower in the foreground symbolizes the Rancho Santa Margarita Lake Tower. Rancho Santa Margarita has the longest city name in California with 20 letters. The title was previously held by La Cañada Flintridge.

Geography
Rancho Santa Margarita is located at 33°38′29″N, 117°35′40″W (33.641518, -117.594524)GR1.According to the United States Census Bureau, the city has a total area of 31.9 km² (12.3 mi²). 31.8 km² (12.3 mi²) of it is land and 0.1 km² (0.04 mi²) of it (0.16%) is water.

Demographics
As of the censusGR2 of 2000, there were 47,214 people, 16,253 households, and 12,417 families residing in the city. The population density was 1,485.7/km² (3,847.6/mi²). There were 16,515 housing units at an average density of 519.7/km² (1,345.9/mi²). The racial makeup of the city was 81.59% White, 1.75% African American, 0.42% Native American, 7.40% Asian, 0.21% Pacific Islander, 4.49% from other races, and 4.15% from two or more races. Hispanic or Latino of any race were 13.00% of the population.
There were 16,253 households out of which 51.4% had children under the age of 18 living with them, 64.7% were married couples living together, 8.5% had a female householder with no husband present, and 23.6% were non-families. 17.7% of all households were made up of individuals and 2.4% had someone living alone who was 65 years of age or older. The average household size was 2.90 and the average family size was 3.35.
In the city the population was spread out with 33.6% under the age of 18, 5.7% from 18 to 24, 41.4% from 25 to 44, 15.9% from 45 to 64, and 3.4% who were 65 years of age or older. The median age was 32 years. For every 100 females there were 96.8 males. For every 100 females age 18 and over, there were 92.9 males.
The median income for a household in the city was $78,475, and the median income for a family was $88,216. Males had a median income of $61,314 versus $40,799 for females. The per capita income for the city was $31,531. About 1.5% of families and 2.9% of the population were below the poverty line, including 3.1% of those under age 18 and 4.2% of those age 65 or over.

Education
The city is served by Saddleback Valley Unified School District and the Capistrano Unified School District. There are three private schools in Rancho Santa Margarita. RSM Intermediate School, one of the most technologically advanced middle schools in the state, serves 7th-8th graders. It is one of the few schools that has a separate theater and school gym. Public Elementary schools include Cielo Vista, Trabuco Mesa, Robinson, Arroyo Vista, and Melinda Heights. Private Elementary and Middle Schools include St. John's Episcopal, Serra Catholic, and Mission Christian. Santa Margarita Catholic High School is a private Roman Catholic high school.

Area
- City 12.3 sq mi (31.9 km²)
- Land 12.3 sq mi (31.8 km²)
- Water 0 sq mi (0.1 km²)
 
Population (2000)
- City 47,214
- Density 3,847.9/sq mi (1,485.7/km²)
Time zone PST (UTC-8)
- Summer (DST) PDT (UTC-7)

City of Rancho Santa Margarita official website