
Sullivan City
- County:
- Hidalgo County
- County Seat:
- No
- Area (mi²):
- 3.589
- State:
- Texas
Sullivan City is a city located in Hidalgo County, Texas. Sullivan City has a 2025 population of 3,892. Sullivan City is currently declining at a rate of -0.08% annually and its population has decreased by -0.43% since the most recent census, which recorded a population of 3,909 in 2020.
The average household income in Sullivan City is $51,672 with a poverty rate of 29.85%. The median age in Sullivan City is 36.1 years: 36.4 years for males, and 33.7 years for females.