Irion County is a county in Texas, United States, on the Edwards Plateau just west of San Angelo. It had a population of 1,513 at the 2020 census and covers 1,052 square miles (2,720 km2) of land, centred near 31°18′N 100°59′W.
Mertzon is the county seat, and its postal code is 76941. The county has one incorporated city and a handful of small unincorporated communities, sits in the Central time zone, and carries FIPS code 48-235.
Towns & Villages in Irion County
Irion County has only one incorporated place — Mertzon, the county seat — alongside a scatter of unincorporated communities and historic place names. “CDP” below marks a census-designated place; “Unincorp.” marks a community or historic locale with no incorporated government.
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Mertzon | City · seat | — | 76941 |
| Barnhart | Unincorp. | — | 76931 |
| Sherwood | Unincorp. | — | — |
| Arden | Unincorp. | — | — |
| Noelke | Unincorp. | — | — |
| Suggs | Unincorp. | — | — |
| Old Burk Place | Unincorp. | — | — |
| Old Freitag Place | Unincorp. | — | — |
Sherwood was the county’s original seat before Mertzon took over in 1936, and it is still an active community rather than a ghost town. Arden, Noelke, Old Burk Place and Old Freitag Place are older ranching-era settlements and post-office names that persist on maps but never incorporated.
ZIP Codes
- 76941 — Mertzon (also serves the county seat area and Sherwood)
- 76931 — Barnhart
The county’s smaller communities — Arden, Noelke, Suggs, Old Burk Place and Old Freitag Place — use the Mertzon or Barnhart ZIP depending on which side of the county they sit on.
Geography
Irion County sits on the eastern Edwards Plateau, a dry, rolling ranching landscape of mesquite and cedar breaks cut by the North and Middle Concho River drainages. Elevation runs from roughly 1,900 feet along the Concho drainages to over 2,400 feet on the plateau’s caprock divides. The county is almost entirely land, with only 0.07 square miles (0.18 km2) of water — there is no significant lake or reservoir within its borders, and rainfall is generally too sparse to sustain one. Much of the ground is underlain by the Spraberry Trend, one of the largest oil fields in the United States by remaining reserves, and the surface is used almost entirely for sheep, goat and cattle ranching.
Irion County borders Tom Green County to the north and east, Schleicher County to the southeast, Crockett County to the southwest, and Reagan County to the west.
Demographics
Irion County had 1,513 residents at the 2020 census, giving a density of roughly 1.4 people per square mile — among the more sparsely settled counties on the Edwards Plateau. Mertzon and Barnhart are its two largest communities. Median household income in Irion County has historically run close to the Texas median of $75,780, reflecting a mixed ranching-and-oilfield economic base rather than the lower incomes typical of poorer rural West Texas counties.
Economy & Local Life
Sheep and cattle ranching built the county and still shape its land use, but oil and gas from the Spraberry Trend, discovered in 1928, has been the dominant revenue source for decades, with drilling activity rising and falling alongside the broader Permian Basin cycle. Mertzon’s school district and county offices are the county seat’s main employers; Barnhart has grown as an oilfield-services hub during drilling upswings, with truck yards, tank farms and worker housing clustered along US 67. Local life centres on the Irion County Independent School District, ranching co-ops, and small-town civic institutions rather than any large commercial district — residents commonly drive to San Angelo for retail, healthcare and larger services.
History
Irion County was formed in 1889 from Tom Green County and named for Robert Anderson Irion, who served as the Republic of Texas’s secretary of state and was also a physician who had earlier served in the Texas Congress. Sherwood served as the first county seat; Mertzon, established along the Kansas City, Mexico and Orient Railway, took over as seat in 1936 as the rail line drew commerce away from the older town, which shrank to a small unincorporated community. Oil discoveries beginning in 1928 later reshaped the county’s economy around the Spraberry Trend, bringing a period of population growth and infrastructure investment that has waxed and waned with oil prices ever since.
Getting There
U.S. Highway 67 and State Highway 137 cross the county through Mertzon, linking it to the region’s main towns.
- San Angelo — 27 miles northeast
- Big Lake — 30 miles southwest
- Eldorado — 28 miles southeast
- Sonora — 45 miles south
San Angelo Regional Airport, in neighboring Tom Green County, is the nearest commercial airport.
Frequently Asked Questions
Where is Irion County?
It is in west-central Texas on the Edwards Plateau, immediately west of San Angelo and Tom Green County.
What is the population of Irion County?
1,513 people at the 2020 census.
How big is Irion County?
1,052 square miles (2,720 km2), almost entirely land.
What is the county seat of Irion County?
Mertzon is the county seat.
How many towns are in Irion County?
Just one incorporated city, Mertzon, plus several small unincorporated communities including Barnhart, Sherwood and Arden.
What ZIP codes are in Irion County?
76941 (Mertzon) and 76931 (Barnhart) cover the county.
What is Irion County’s main industry?
Ranching and oil and gas production from the Spraberry Trend, one of the country’s largest oil fields by remaining reserves.
More counties in this state: Towns and villages in Texas.