South Pasadena, CA has a population of 25,936 and is the 1,659th largest city in the United States. The population density is 7,616 per sq mi which is 3177% higher than the California average and 8306% higher than the national average. The median age in South Pasadena is 40 which is approximately 11% higher than the California average of 36. In South Pasadena, 54% of the population over 15 years of age are married, 61% speak English and 11% speak Spanish. 50% of South Pasadena residents were born in California, 21% were born out of state, 2% were born outside of the United States and 27% were foreign born.