Monument, CO has a population of 6,346 and is the 5,554th largest city in the United States. The population density is 940 per sq mi which is 1787% higher than the Colorado average and 937% higher than the national average. The median age in Monument is 35 which is approximately 4% lower than the Colorado average of 36. In Monument, 71% of the population over 15 years of age are married, 91% speak English and 5% speak Spanish. 25% of Monument residents were born in Colorado, 63% were born out of state, 4% were born outside of the United States and 8% were foreign born.