St. Helena, CA has a population of 5,995 and is the 5,762nd largest city in the United States. The population density is 1,202 per sq mi which is 417% higher than the California average and 1227% higher than the national average. The median age in St. Helena is 48 which is approximately 33% higher than the California average of 36. In St. Helena, 63% of the population over 15 years of age are married, 66% speak English and 29% speak Spanish. 51% of St. Helena residents were born in California, 27% were born out of state, 1% were born outside of the United States and 21% were foreign born.