Benton County, Oregon

Benton County is a county in Oregon, United States, in the Willamette Valley and home to Oregon State University. It had a population of 95,184 at the 2020 census and covers 679 square miles (1,760 km2) centred near 44°29′N 123°26′W.

Corvallis is the county seat, and its postal code is 97330. The county has four incorporated cities — plus the northern edge of a fifth — six census-designated places, and a scatter of unincorporated rural communities. Benton County sits in the Pacific time zone and carries FIPS code 41003.

Towns & Villages in Benton County

The table below lists 22 named places in Benton County. Four are incorporated cities: Corvallis (the seat), Adair Village, Monroe, and Philomath; the northern portion of Albany also lies within the county, though the city itself is centred in neighboring Linn County. Six are census-designated places (CDP), and the remainder are unincorporated communities and rural crossroads (Unincorp.).

North Albany is a populous, largely residential district on the north bank of the Willamette River that was annexed into the city of Albany in stages; it is listed here separately because it long appeared as its own community on maps of the county. Albany itself is split between Linn County to the east and a slice of Benton County to the west, so only the Benton-side population is unverified and shown as — above.

ZIP Codes

• 97330 — Corvallis (also serves Adair Village)
• 97331 — Corvallis, Oregon State University campus station
• 97370 — Philomath
• 97456 — Monroe (also serves Alpine)
• 97324 — Alsea
• 97326 — Blodgett
• 97361 — Kings Valley
• 97321 — Albany (Linn County post office, also covers the Benton County portion of the city)

Smaller unincorporated communities such as Wren, Lewisburg, Dry Creek, and Summit use a nearby town’s ZIP code rather than one of their own.

Geography

Benton County straddles the transition between the flat farmland of the Willamette Valley in its eastern third and the forested foothills of the Coast Range across its western two-thirds. The Willamette River forms part of the county’s eastern edge, and the Marys River, which flows through Philomath and Corvallis, is the county’s principal interior waterway. Elevations climb from valley floor near sea level along the Willamette to over 3,700 feet in the Coast Range near Marys Peak, the tallest point in the Oregon Coast Range.

Benton County borders four other Oregon counties: Polk County to the north, Linn County to the east, Lane County to the south, and Lincoln County to the west.

Demographics

Benton County had 95,184 residents at the 2020 census, giving it a density of about 141 people per square mile of land. Corvallis, the seat, is by far the largest community, followed by Philomath. A large share of the population is tied to Oregon State University, which enrolls tens of thousands of students who count toward the county’s census figures while living in Corvallis. Median household income in the county runs close to the Oregon median of $80,160, reflecting a mix of university salaries, health care jobs, and agricultural income in the rural west of the county.

Economy & Local Life

Oregon State University is the county’s largest single employer and its economic anchor, drawing research funding, a teaching hospital-adjacent health care sector, and a large student population that supports Corvallis’s retail and rental markets. Hewlett-Packard has operated a long-standing manufacturing and research site in Corvallis since the 1970s. Outside the university corridor, Benton County’s economy is agricultural: grass seed, hazelnuts, and vineyards fill the valley floor, while timber remains important in the Coast Range foothills to the west. Corvallis hosts Da Vinci Days, an annual summer festival of art, science, and technology, each July.

History

Benton County was created by the Oregon Territorial Legislature on December 23, 1847, and named for Thomas Hart Benton, the Missouri senator who championed American settlement of the Oregon Country even though he never visited it. Corvallis briefly served as the capital of the Oregon Territory in the 1850s before the seat of government moved permanently to Salem. Oregon State University traces its roots to Corvallis College, chartered in 1858 and later designated the state’s land-grant institution in 1868.

Getting There

US Highway 20 and US Highway 34 cross the county east–west, connecting Corvallis and Philomath to Interstate 5 in Albany and to the Oregon coast near Waldport. Oregon Route 99W runs north–south through Corvallis toward Albany and McMinnville.

• Albany — 10 miles east
• Salem — 40 miles north
• Eugene — 40 miles south
• Portland — 85 miles north

The nearest commercial air service is Eugene Airport, about 45 miles south of Corvallis; Portland International Airport, roughly 85 miles north, offers a much larger schedule of flights.

Frequently Asked Questions

Where is Benton County, Oregon?
It lies in the Willamette Valley of western Oregon, between the valley floor to the east and the Coast Range to the west, roughly 40 miles south of Salem and 40 miles north of Eugene.

What is the population of Benton County?
Benton County had 95,184 residents at the 2020 census.

How big is Benton County?
The county covers 679 square miles (1,760 km2), of which 676 square miles are land.

What is the county seat of Benton County?
Corvallis is the county seat and home to Oregon State University.

How many towns are in Benton County?
The county has four incorporated cities — Corvallis, Adair Village, Monroe, and Philomath — plus a slice of Albany, six census-designated places, and a number of smaller unincorporated communities.

What ZIP codes are in Benton County?
Main ZIP codes include 97330 and 97331 (Corvallis), 97370 (Philomath), 97456 (Monroe), and 97324 (Alsea).

Why is it called Benton County?
It was named after Thomas Hart Benton, the U.S. senator from Missouri who advocated for American control of the Oregon Country in the 1840s.

More counties in this state: Towns and villages in Oregon.