County · code 41003
Benton CountyOregon
Benton County is a county in Oregon with its county seat in Corvallis. It was created on December 23, 1847, from Polk County and named after Thomas Hart Benton.
- Founded1847
- County seatCorvallis
- Named forThomas Hart Benton
- Land area675 sq mi + 3 sq mi water
- Population95,184 2020 Census
- Parcels mapped107,939 checked 16 October 2026
Where it is
Benton on the map of Oregon
Oregon has 36 counties and county equivalents, each with its own records office. Shapes with a page are links.
History
Formed in 1847 from Polk County
An old deed may name a county that no longer exists, or a boundary that has since moved.
Benton County was created by the Provisional Legislature of Oregon Territory from area formerly part of Polk County. The county lost territory to the creation of Umpqua and Lane counties in 1851, and again lost land to Lincoln County in 1893 and 1927, though it gained land from Lincoln County in 1949. Benton became an Oregon county when the state was admitted to the Union in 1859 and Oregon Territory was eliminated.
- 1847Benton County created Benton created by the Provisional Legislature of Oregon Territory from area formerly part of Polk. On 20 December 1847 the Journal of the Provisional Legislature recorded the passage of an act to redefine the boundaries of Polk. No such act appears within the session laws, but the definition of Benton depends on an earlier change having been made to the south line of Polk. · Ore. Terr. Laws, general and local, 1843-1849, p. 50; Holman, 28-30; Oregon Archives, 237
- 1851Lost territory Benton lost to creation of Non-County Area 4 when the county's southern line redefined. This change apparently made in preparation for creation of Umpqua (extinct) on 24 January 1851, and creation of Lane on 28 January 1851.to Umpquato Lane· Ore. Terr. Laws 1850, 2nd sess., p. 34
- 1859Became part of Oregon Benton became an Oregon county when the state of Oregon was admitted to the Union and Oregon Territory was eliminated. · U.S. Stat., vol. 11, ch. 33[1859], secs. 1-2/pp. 383-384; Ore. Laws 1860, 1st reg. sess., pp. 28-30
- 1893Lost territory Benton lost to creation of Lincoln. · Ore. Laws 1893, gen., 17th reg. sess., pp. 68-77
- 1923Gained territory Benton gained from Lane. · Ore. Laws 1923, gen., 32nd reg. sess., ch. 92/pp. 129-131
- 1927Lost territory Benton lost to Lincoln when boundary was redefined to run along range line. · Ore. Laws 1927, gen., 34th reg. sess., ch. 278/pp. 350-351
- 1949Gained territory Benton gained from Lincoln. · Ore. Laws 1949, gen., 45th reg. sess., ch. 401/pp. 593-596
Land and parcels
What the maps cover in Benton
Who publishes each layer, how good it is, and when we last checked.
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Parcels Good enough
Lot lines and tax-map numbers for 107,939 parcels from Benton County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 16 October 2026 -
Address points Official
One point per address, 41,473 in all from State of Oregon — Department of Administrative Services Geospatial Enterprise Office (GEOHub) with Oregon Department of Emergency Management 9-1-1 program.
edited 16 January 2026 · checked 13 October 2026 -
Buildings Reference
Roof outlines traced from aerial imagery from FEMA Response Geospatial Office with Oak Ridge National Laboratory (ORNL). Good for seeing what is on a lot; not accurate enough to set a fence from.
checked 18 October 2026
- Official
- from the office that keeps the record
- Good enough
- a reliable statewide or national copy
- Fallback
- a guide only; check the official record
- Missing
- nothing public found yet
People and land
Benton by the Census
Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.
Rules and offices
Benton County's official site
We have found the county's site but not its offices yet; start there.
County government
- County government
The official website of Benton County.
See your own lot on these maps
Open Benton County on Parcel Chart's free map and click your parcel. Save it with a free account; the full record of your place (site map, projects, documents) is Pro, in early access.
Questions
Common questions about Benton County
- When was Benton County founded?
- Benton County was founded in 1847, formed from Polk County, and named after Thomas Hart Benton.
- What is the county seat of Benton County?
- The county seat of Benton County is Corvallis.
- Is there an online parcel map for Benton County?
- Yes. Benton County publishes a parcel map of 107,939 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has Benton County's boundary or name changed?
- Benton County was created in 1847 from Polk County. Since then the Atlas of Historical County Boundaries records 6 later changes, chiefly involving Lincoln County, Lane County and Umpqua County.
- Is my lot in a flood zone?
- We do not have flood maps for Benton County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby