Sullivan City, Texas
Sullivan City is a small city in western Hidalgo County, about 20 miles west of McAllen along the Rio Grande in the Rio Grande Valley of deep South Texas. It lies in the flat, intensively farmed delta country near the river, where citrus, vegetables, and other crops grow in the warm subtropical climate. The town sits within the string of border communities that line the lower Rio Grande.
Place essentials
Official Census snapshot- Census place type
- City
- July 2025 population
- 3,891
- Change from 2020 base
- -0.3%
- Land area
- 3.6 sq. mi.
- County footprint
- Hidalgo County
Place type, county footprint, and land area use the Census Bureau's January 1, 2025 geography. Population uses Vintage 2025 estimates through July 1, 2025; change compares that estimate with the April 1, 2020 estimates base. Geography file | Population file
Property here runs through the appraisal district and tax office for Hidalgo County. The homestead exemption, appraisal cap, protests, and any MUD, PID, or special districts all sit at the parcel level.
Official routes
Use the office for the parcel address; a mailing city is not always the governing city.
County context
What to know around Sullivan City
County lines carry much of the property, land, water, and outdoors context around Sullivan City.
County History
Hidalgo County Was Formed in 1852 and Named for a Mexican Hero
The county was established in 1852 and named for Miguel Hidalgo y Costilla, who began Mexico's fight for independence from Spain.
Property Tax Basics
Two Separate Offices Handle Your Property Taxes
Hidalgo County has one office that values your property and a different office that collects the taxes, so you need to know which to contact.
Settlement History
Spanish Ranchers Settled This Area More Than 275 Years Ago
The lower Rio Grande Valley was settled by Spanish ranching families in 1749 under José de Escandón, making it one of the older continuously settled regions in Texas.
Nearby
Places near Sullivan City
Nearby counties
Local notes for nearby counties
Next steps for Sullivan City
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