Jefferson County, Idaho Genealogy
Jefferson County Courthouse
Rigby, ID 83442-0538
Phone: (208) 745-7756
Fax: (208) 745-6636
1913--Jefferson County was created 18 February 1913 from Fremont County. Named for Thomas Jefferson, 3rd U.S. President. A part of the county was taken to create Butte County 6 February 1917. County seat: Rigby 
Many of the older court, land, naturalization, probate, pension, and vital records for Jefferson County have been microfilmed and are available at the Family History Library in Salt Lake City and through their family history centers. They are also available at the Idaho State Archives in Boise. Details of the county records in these respective institutions can be obtained from their online catalogs or listings. Original records which have been microfilmed and more recent records are in the county courthouse in Rigby.
There are many cemeteries in Jefferson County. For a list of those that have been identified, and links to transcriptions and/or photographs of tombstones, go to Jefferson County, Idaho Cemetery Records.
For the cemeteries in or immediately adjacent to the cities, please see the city pages for the cities listed above.
For a summary of census records for the state of Idaho, see Idaho Census Records.
The Church of Jesus Christ of Latter-Day Saints (Mormons)
The following are local congregations (wards) of The Church of Jesus Christ of Latter-Day Saints which existed in Jefferson County, Idaho prior to 1950. Many of the original records of these church units are in the Historical Library in Salt Lake City. Many of the membership records covering these units from the date of their creation to about 1948 have been microfilmed and are available at the Family History Library in Salt Lake City. An entire set of the Idaho local LDS church records are at BYU-Idaho Library and the Idaho Falls Regional Family History Center.
County Commissioners' Records
The minute books of the County Commissioners contain interesting tidbits of history about the county as well as the names of individuals appealing to the County Commissioners for action on issues of concern to them. Minutes of those meetings were recorded from the formation of the county, for most counties. Some counties now post the minutes of current meetings online.
Most of these records have been preserved in the county courthouses of the State of Idaho. Few have been microfilmed. Contact the county clerk for information about years covered and availability.
- A digital Jefferson County Idaho map is available online.
- Map of Jefferson County, Idaho is available online.
World War I draft registration cards, 1917-1918, for Jefferson County have been microfilmed. Copies of these records are available at the Family History Library (their microfilm number 1452216) and are also available online at Ancestry.com, for a subscription fee. The original cards are maintained in the Southeast Regional Archives of the National Archives and Records Administration (NARA) in East Point, Georgia and have been microfilmed by the National Archives as their Microcopy M1509.
Often overlooked by the genealogist, this group of volumes may contain affidavits for citizenship, final disposition of estates, divorce decrees, and many other types of valuable documents. The content varies from county to county, year to year and from clerk to clerk. When the estate case files, civil or criminal files are not available or have been destroyed, you may find key documents recorded here. Most counties will have an index to this series and it is a must search if the information you are seeking is not found elsewhere.
- Jefferson Star
The existing original probate records for Jefferson County should be available in the county courthouse at Rigby, Idaho, and can be viewing by visiting there.
The Idaho State Archives has microfilmed some of the earlier Jefferson County probate records, and these can be viewed at the Archives in Boise, Idaho.
The Family History Library in Salt Lake City, Utah has made microfilm copies of some of Jefferson County probate records. Microfilm copies are available in Salt Lake City and in any of the Family History Centers.
Any existing tax assessment rolls for Jefferson County should be in the courthouse in Rigby and would need to be accessed by visiting there.
Birth records, 1914 to present, for individuals born in Jefferson County are included in and recorded at the state level. These records are restricted for a period of one hundred years from the time of the individual's birth but can be obtained by following the guidelines as issued by the State of Idaho. See the Vital Records section under the subject Idaho for more details.
All of the early marriage records for Jefferson County have been microfilmed and are available at the Idaho State Archives in Boise (PARL), the Family History Library in Salt Lake City, Utah and the BYU-Idaho Library in Rexburg. Included are:
• Marriage Records Books, 1914-1932 • Index to Marriage Records, 1914-1932.
Marriages from other sources.
Over 2200 marriages from 1914-1952, are listed on the Western States Marriage Index.
After 1914, deaths occuring in Jefferson County are included in the state-wide registration program. These records are restricted for a period of fifty years from the time of the individual's death but can be obtained by following the guidelines as issued by the State of Idaho. See the Vital Records section under Idaho for details.
Copies of death certificates from 1911-1954 are on microfilm and can be used at the Idaho State Archives, the Family History Library, BYU-Idaho University Library in Rexburg and several other locations.
A state-wide index to Idaho Deaths, 1911-1956 is available online. Efforts to expand this index to 1960 are underway.
Deaths from other sources.
There is one other significant source for death information for this county. It is the Eastern Idaho Death Index.
Societies and Libraries
Many public libraries provide internet access to sites of value to the family historian. Some have special collections of historical and cultural interest, as well. The following libraries may have some resources of value, but use of some or all of them may require a visit to the library.
- Lewisville Public Library
3453 E 480 N
Lewisville, ID 83431
Phone: (208) 754-8608
- Jefferson County District Library
623a N 3500 E
Menan, ID 83434
Phone: (208) 754-0021
- Ririe Public Library
464 Main St
Ririe, ID 83443
Phone: (208) 538-7974
- Rigby Public LIbrary
110 N State St
Rigby, ID 83442
Phone: (208) 745-8231
- Roberts Public Library
650 N 2870 E
Roberts, ID 83444
Phone: (208) 228-2210
- Museum Jefferson County Historical Society
118 West 1st South, Rigby, ID 83442-1303
- The Jefferson County ID GenWeb Project, a member of The IDGenWeb Project, an affiliate of The USGenWeb Project
- Family History Library Catalog
- Jefferson County, Idaho Genealogy and Family History (Linkpendium)
- The Handybook for Genealogists: United States of America,10th ed. (Draper, UT:Everton Publishers, 2002).
- Idaho State Historical Society Reference Series, Number 10, Counties and County Seats, Reissued July, 1991.