Weldon Spring Heights, MO has a population of 109 and is the 26,688th largest city in the United States. The population density is 1,226 per sq mi which is 1319% higher than the Missouri average and 1253% higher than the national average. The median age in Weldon Spring Heights is 58 which is approximately 52% higher than the Missouri average of 38. In Weldon Spring Heights, 86% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 73% of Weldon Spring Heights residents were born in Missouri, 24% were born out of state, 3% were born outside of the United States and 0% were foreign born.