Cortez, CO has a population of 8,683 and is the 4,390th largest city in the United States. The population density is 1,371 per sq mi which is 2653% higher than the Colorado average and 1413% higher than the national average. The median age in Cortez is 37 which is approximately 1% higher than the Colorado average of 36. In Cortez, 50% of the population over 15 years of age are married, 84% speak English and 6% speak Spanish. 42% of Cortez residents were born in Colorado, 55% were born out of state, 0% were born outside of the United States and 4% were foreign born.