New Castle is a city located in Henry County Indiana. It is also the county seat of Henry County. With a 2020 population of 16,891, it is the 51st largest city in Indiana and the 2134th largest city in the United States . New Castle is currently declining at a rate of -0.65% annually and its population has decreased by -6.75% since the most recent census, which recorded a population of 18,114 in 2010. New Castle reached it's highest population of 21,215 in 1970. Spanning over 7 miles, New Castle has a population density of 2,298 people per square mile.
The average household income in New Castle is $48,154 with a poverty rate of 22.50%. The median rental costs in recent years comes to $707 per month, and the median house value is $73,300. The median age in New Castle is 40.1 years, 37 years for males, and 42.7 years for females.