Benton County


yellow flowers next to waterfall
Flowers at Parker Creek Falls on Marys Peak. (Oregon State Archives Photo)
County Seat: 205 NW Fifth St., Corvallis 97330
Phone: 541-766-6800 (General); 541-766-6859 (Trial Court Administrator)
Fax: 541-766-6893


Population (2020): 94,665
Established: Dec. 23, 1847
Elev. at Corvallis: 224'
Area: 679 sq. mi.
Average Temp.: January 39.3° July 65.6°
Assessed Value: $9,545,994,419
Real Market Value: $18,822,318,695
(includes the value of non-taxed properties)
Annual Precipitation: 42.71"
Economy: Agriculture, forest products, research and development, electronics and wineries

Related Resources

Oregon county map with Benton County shaded
"County QuickFacts" (population and economic data from U.S. Census Bureau)
County Seat Map (from Google Maps)
County Map (from ODOT)

Incorporated Cities

Points of Interest

Benton County Courthouse, Oregon State University Campus, Benton County Museum (Philomath), Alsea Falls, Mary’s Peak, William L. Finley National Wildlife Refuge, Peavy Arboretum, McDonald Forest, Jackson-Frazier Wetland, Beazell Memorial Forest & Education Center

History and General Information 

Benton County was created from Polk County by an act of the Provisional Government of Oregon in 1847. It is one of seven counties in the United States to be named after Senator Thomas Hart Benton of Missouri, a longtime advocate of the development of the Oregon Territory. The county is located in an area originally inhabited by the Klickitat Tribe, who rented the area from the Kalapuya Tribe for use as hunting grounds. At that time, the boundaries began at the intersection of Polk County and the Willamette River, ran as far south as the California border and as far west as the Pacific Ocean. Later, portions of Benton County were taken to form Coos, Curry, Douglas, Jackson, Josephine, Lane and Lincoln Counties, leaving it in its present form with 679 square miles of land area.

A substantial portion of the nation’s research in forestry, agriculture, engineering, education and the sciences takes place at OSU located at the county seat in Corvallis.

County Officials

Commissioners—Xanthippe “Xan” Augerot (D) 2025, Nancy Wyse (D) 2025, Pat Malone (D) 2023; Dist. Atty. John Haroldson 2025; Assess. Tami Tracy; Clerk James Morales; Sheriff Scott Jackson 2023; Surv. Joe Mardis; Tax Collector Mary Otley; Public Information Officer Alyssa Rash​