Lafayette, CO has a population of 27,053 and is the 1,598th largest city in the United States. The population density is 2,871 per sq mi which is 5027% higher than the Colorado average and 3069% higher than the national average. The median age in Lafayette is 39 which is approximately 6% higher than the Colorado average of 36. In Lafayette, 57% of the population over 15 years of age are married, 83% speak English and 11% speak Spanish. 35% of Lafayette residents were born in Colorado, 53% were born out of state, 1% were born outside of the United States and 11% were foreign born.