
Newcastle
- County:
- Iron County
- County Seat:
- No
- Area (mi²):
- 3.978
- State:
- Utah
Newcastle is a CDP located in Iron County, Utah. Newcastle has a 2025 population of 357. Newcastle is currently growing at a rate of 2% annually and its population has increased by 9.51% since the most recent census, which recorded a population of 326 in 2020.
The average household income in Newcastle is $84,425 with a poverty rate of 0%. The median age in Newcastle is 63.2 years: 68.3 years for males, and 42.8 years for females.