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Benton County, Washington

Benton County was founded on March 08, 1905 from Yakima County and Klickitat County. The county was named in honor of Thomas Hart Benton (1782–1858), a Missouri U.S. Senator.

The Benton County Seat is situated in Prosser and the county government website is

Locations bordering Benton County are Grant CountyFranklin CountyWalla Walla CountyUmatilla County, Oregon, Morrow County, Oregon, Klickitat CountyYakima County.

Benton County vital records can be found at the Washington Office of Vital Records has copies of birth, marriage, divorce and death records. There is a fee for each copy requested. Please refer to the information to the Statewide Vital Records in Washington for current fees and application process.

You can search online for Benton County Birth, Marriage, Divorce or Death Records. You can also Order Electronically Online or can download an application for Washington Birth or Death Certificate and Marriage or Divorce Certificate Applications to mail.

Benton County has Federal Census Schedules to assist in researching your family tree. Federal government Population Schedules exist for 1910192019301940. You’ll find free down loadable in addition to printable census forms that can help with your research.

Benton County Society and Family History Resources

A list of Benton County Historical  and Genealogical Societies, Forums, Message Boards, Libraries, Archives.

  • Washington State Genealogy Network (
  • Central Regional Branch—Washington State Archives, Central Washington University, MS-7547, Ellensburg, WA 98926-7547
  • Benton County Historical Society, Inc., PO Box 591, Prosser, WA 99350. Phone 509-786-3842.
  •  East Benton County Historical Society, 205 Keewaydin Drive, PO Box 6964, Kennewick, WA 99336. Phone 509-582-7704. Operates the East Benton County Historical Museum.
  • Tri-city Genealogical Society, PO Box 1410, Richland, WA 99352-1410. Membership available. Tri-City Genealogical Society’s holdings are located at the Richland Family History Center.
  • Washington State University Tri-Cities Library, Max E. Benitz Library, 100 Sprout Rd, Richland, WA; 99352-1643. Phone 509-372-7430. Fax 509-372-7281.
  • Benton/Franklin County Law Library, Columbia Basin College Library, 2600 N 20th Ave, Pasco, WA; 99301. Phone 509-547-0511 ext. 2290.
  •  Kennewick Family History Center, 895 W Gage Blvd, Kennewick, WA. Phone 509-628-8332.
  • Prosser Family History Center, 1835 Highland Drive, Prosser, WA. Phone 509-786-3860.
  • Richland Family History Center, 1314 Goethals, Richland, WA 99352. Phone 509-946-6637.
  •  Tri-City Herald Library, PO Box 2608, Tri Cities, WA 99302. Not generally open to the public.
  • Mid-Columbia Library, 4101 E Lattin Rd, West Richland, WA 99353. Phone 509-627-0285. Fax 509-545-2054. The following are branches of this library system:
    • Benton City Branch, 708 Ninth St, Box 369, Benton City, WA 99320. Phone 509-588-6471.
    • Kennewick Branch, 405 S Dayton, Kennewick, WA 99336-5690. Phone 509-586-3156.
    • West Benton Branch, 614 Sixth St, Prosser, WA 99350. Phone 509-786-3777. Fax 509-786-3777.
    • West Richland Branch, 3803 W Van Giesen, West Richland, WA 99353. Phone 509-967-3191.
  • Prosser Public Library, 902 7th St, Prosser, WA 99350-1454. Phone 509-786-2533. Collection includes northwest history materials and microfilm of local newspapers back to 1903.
  • Richland Public Library, 955 Northgate, Richland, WA 99352-3539. Phone 509-942-7450.
  • Benton County, Washington Message Boards (
  • Benton County, Washington Genealogy Forum (
  • Washington State Digital Archives (
  • USGenWeb Archives for Benton County (

Benton County Courthouse and Government Records

Genealogist often forget the benefits of Benton County court, probate, and land files as a source of genealogy information and facts. Buried away in Washington courthouses and archives everywhere tend to be the desires and frustrations of countless Washington men and women.

The possibilities are great that your ancestors have left a in-depth record of at least a few factors of their lives in the Benton County court records. Even if your forebears is not discussed in a Court case, contemplate all of the other methods which could have lead to her or him appearing in court records.

The dates pointed out below could be the first noted records for this particular county.

  • Benton County Courthouse (all departments listed below are located here, unless otherwise noted)
    • Address: 620 Market St, Prosser, WA 99350
    • Courthouse hours: 8:00 am – 5:00 pm
  • Benton County Auditor
    • Birth and Death Records: 1905 to 1907
    • Marriage Records: 1905
    • Land Records: 1885
  • Benton County Clerk
    • Court Records: 1884
    • Probate Records: 1884

Benton County Links

The following are links to Family history and genealogy, Records and Resources pertaining to Benton County. Most of these genealogy links fall into 3 categories: Commercial Sites, Private Sites or Organization Sites. Some have free access some require a fee. This is simply a directory that has been gathered or submitted. I do not endorse or promote one genealogy site above another. Feel free to present your own favorite Benton County genealogy or family history affiliated sites.

Benton Co. WA Books, Newspapers & Publications

Benton Co. WA Birth, Marriage & Death Records

Benton Co. WA Court, Probate Land and Tax Records

Benton Co. WA Census Records

Benton Co. WA Church & Cemeteries

Benton Co. WA Family Websites, Pictures & Histories

Benton Co. WA General and History Websites

Benton Co. WA Immigration & Naturalization

Benton Co. WA Maps, Atlases & Gazetteers

Benton Co. WA Military Records

Benton Co. WA Schools & Directories