Red Cliff, CO has a population of 246 and is the 23,511th largest city in the United States. The population density is 1,048 per sq mi which is 2005% higher than the Colorado average and 1057% higher than the national average. The median age in Red Cliff is 39 which is approximately 8% higher than the Colorado average of 36. In Red Cliff, 56% of the population over 15 years of age are married, 79% speak English and 20% speak Spanish. 55% of Red Cliff residents were born in Colorado, 40% were born out of state, 0% were born outside of the United States and 4% were foreign born.