Buellton, CA has a population of 5,021 and is the 6,454th largest city in the United States. The population density is 3,174 per sq mi which is 1140% higher than the California average and 3403% higher than the national average. The median age in Buellton is 45 which is approximately 25% higher than the California average of 36. In Buellton, 68% of the population over 15 years of age are married, 74% speak English and 23% speak Spanish. 57% of Buellton residents were born in California, 25% were born out of state, 1% were born outside of the United States and 17% were foreign born.