Umatilla County, Oregon

Umatilla County
Stafford Hansell Government Center in Hermiston
Stafford Hansell Government Center in Hermiston
Map of Oregon highlighting Umatilla County
Location within the U.S. state of Oregon
Map of the United States highlighting Oregon
Oregon's location within the U.S.
Coordinates: 45°22′30″N 118°45′05″W / 45.375131°N 118.7513661°W / 45.375131; -118.7513661
Country United States
State Oregon
FoundedSeptember 27, 1862
Named forUmatilla River
SeatPendleton
Largest cityHermiston
Area
 • Total3,231 sq mi (8,370 km2)
 • Land3,216 sq mi (8,330 km2)
 • Water16 sq mi (40 km2)  0.5%
Population
 (2020)
 • Total80,075
 • Estimate 
(2023)
80,053 Decrease
 • Density20/sq mi (9/km2)
Time zoneUTC−8 (Pacific)
 • Summer (DST)UTC−7 (PDT)
Congressional district2nd
Websitewww.co.umatilla.or.us

Umatilla County (/ˌjuːməˈtɪlə/) is one of the 36 counties in the U.S. state of Oregon. The population of 81,826 ranks it as the 14th largest in Oregon, and largest in Eastern Oregon.[1] Hermiston is the largest city in Umatilla County, but Pendleton remains the county seat.[2] Umatilla County is part of the Hermiston-Pendleton, OR Micropolitan Statistical Area, which has a combined population of 94,833.[3] It is included in the eight-county definition of Eastern Oregon.

The county is named for the Umatilla River.

  1. ^ "Population Estimate Reports". Portland State University. December 18, 2023. Retrieved December 19, 2023.
  2. ^ "Find a County". National Association of Counties. Retrieved June 7, 2011.
  3. ^ "Population Estimate Reports". Portland State University. December 18, 2023. Retrieved December 19, 2023.