Jefferson County Historical Society
- Nonprofit organization dedicated to preserving and passing on the history and culture of the area. Includes events and links to area museums. Located in Fairbury.
- http://www.jeffersoncountyhistory.com/

Jefferson County Economic Development
- Dedicated to promote, foster, encourage and aid the location and development of business, trades and industry in the county. Includes community profiles, list of board members, and information about attractions, lodging, museums and historical sites.
- http://www.visitjeffersoncounty.com/

Jefferson Co. Genealogical Society
- Formed in 1996. Provides information about membership, calendar of events and a list of available publications for sale.
- http://www.rootsweb.com/~nejeffgs/

The Political Graveyard: Jefferson County, Nebraska
- Database provides brief biographies of politicians who lived or died in the county, a cemetery list, and political history.
- http://politicalgraveyard.com/geo/NE/JF.html

Jefferson County - NEGenWeb
- Provides a history of the county and a digital library which contains online genealogy data and indexes. Join the county's mailing list.
- http://www.rootsweb.com/~nejeffer/

Jefferson County, Nebraska
- Official county government site, offering information about elected officials and services provided by county departments.
- http://www.co.jefferson.ne.us/

Nebraska Institute of Agriculture & Natural Resources
- Jefferson County Extension Education page with information to assist farmers, ranchers and State rural communities negotiate changing agricultural economies.
- http://jefferson.unl.edu/