New Castle is a city located in Colorado. With a 2020 population of 5,160, it is the 80th largest city in Colorado and the 4657th largest city in the United States. New Castle is currently growing at a rate of 1.34% annually and its population has increased by 14.21% since the most recent census, which recorded a population of 4,518 in 2010. Spanning over 3 miles, New Castle has a population density of 2,050 people per square mile.
The average household income in New Castle is $100,034 with a poverty rate of 3.34%. The median rental costs in recent years comes to $1,454 per month, and the median house value is $320,400. The median age in New Castle is 32.3 years, 35.1 years for males, and 31.4 years for females. For every 100 females there are 88.9 males.