Wellington, CO has a population of 7,409 and is the 4,972nd largest city in the United States. The population density is 2,162 per sq mi which is 4243% higher than the Colorado average and 2286% higher than the national average. The median age in Wellington is 33 which is approximately 10% lower than the Colorado average of 36. In Wellington, 68% of the population over 15 years of age are married, 95% speak English and 4% speak Spanish. 47% of Wellington residents were born in Colorado, 48% were born out of state, 1% were born outside of the United States and 4% were foreign born.