Gaines County Texas map
32.74° N · 102.63° W · County seat: Seminole · 1,502 sq mi
Gaines County is sand country — loose, deep sandy soils on the southwestern shelf of the Llano Estacado that turn out to be ideal for peanuts and irrigated cotton, and that sit on top of one of the older producing corners of the Permian Basin. It is regularly the top peanut county in Texas and among the top cotton counties, and at 1,502 square miles it is the largest county on the South Plains.
Seminole sits at the crossing of US-62/180 and US-385. The western county line is the New Mexico state line.
Where Gaines County is
Gaines is on the Texas–New Mexico line, with Lea County, New Mexico, along its entire western boundary. Inside Texas it borders Terry and Yoakum to the north, Dawson to the east, Martin to the southeast and Andrews to the south.
The county sits between two economies and belongs to both. Midland is 61 miles southeast and Odessa 64 miles southeast, the Permian Basin cities its oil business answers to. Lubbock is 73 miles northeast, the South Plains city its farm business answers to. Seminole is 30-odd miles from Hobbs, New Mexico, on US-62/180.
Cities and towns
| Place | Type | 2020 population in county |
|---|---|---|
| Seminole (county seat) | City | 7,033 |
| Seagraves | City | 2,153 |
Denver City, on the northwestern edge of the area, lies mostly in Yoakum County and is counted there.
Gaines is one of the few rural High Plains counties that is growing. Its 2024 estimate of 22,892 is about 6 percent above the 2020 count, at a time when most of its neighbors are shrinking. A large Low German-speaking Mennonite community around Seminole, whose families began arriving from colonies in northern Mexico in the 1970s and have kept coming since, accounts for much of that growth and for a good share of the county's farm operators. The community also put Gaines County in national news in 2025, when a measles outbreak centered here became the largest in the United States in decades.
Roads
- US-62 / US-180 – run together east–west through Seminole, east to Lamesa in Dawson County and west into New Mexico toward Hobbs.
- US-385 – the north–south route, south to Andrews and Odessa, north through Seagraves toward Brownfield.
- SH-214 – north from Seminole toward Denver City and the Yoakum County oil field towns.
- SH-83 – northeast toward the Terry County line.
- SH-115 – east toward Welch and the Dawson County line.
Peanuts, cotton and the oil under the sand
The sandy soils that define the county are not much good for anything that needs to hold water at the surface, but they drain well, warm early and let a peanut crop be dug cleanly — which is why Gaines became the center of the Texas peanut industry and why buying points and shelling operations concentrate around Seminole. Cotton is the larger acreage; the two rotate. All of it depends on wells into the Ogallala aquifer, which is thinner on this southwestern edge than it is farther north, so irrigation efficiency here is not an abstraction but a constraint growers work under every season.
Underneath, the county produces oil and gas from the Permian's northwestern shelf. The big field in this corner of Texas is the Wasson field around Denver City, straddling the Gaines–Yoakum line, one of the largest ever discovered in the state and one of the earliest sites in the world where carbon dioxide was injected to push more oil out of an aging reservoir. Pump jacks and center pivots share the same sections across the northern third of the county.
Gaines County was cut out of the Bexar District in 1876 and named for James Gaines, a merchant and ferry operator on the Sabine who signed the Texas Declaration of Independence — a name from the far eastern edge of Texas attached to a county on the far western one. It did not organize a government until 1905.