Lamar, CO has a population of 7,662 and is the 4,851st largest city in the United States. The population density is 1,482 per sq mi which is 2877% higher than the Colorado average and 1536% higher than the national average. The median age in Lamar is 36 which is approximately 2% lower than the Colorado average of 36. In Lamar, 57% of the population over 15 years of age are married, 84% speak English and 15% speak Spanish. 64% of Lamar residents were born in Colorado, 28% were born out of state, 0% were born outside of the United States and 8% were foreign born.