In the Nebraska license plate system, Dundy County is represented by the prefix 76 (it had the seventy-sixth-largest number of vehicles registered in the county when the license plate system was established in 1922).
Dundy County lies at the lower SW corner of Nebraska. Its west boundary line abuts the east line of the state of Colorado, and its south boundary line abuts the north boundary line of the state of Kansas. According to the US Census Bureau, the county has an area of 921 square miles (2,390 km2), of which 920 square miles (2,400 km2) is land and 1.2 square miles (3.1 km2) (0.1%) is water.[8]
There were 961 households, out of which 27.80% had children under the age of 18 living with them, 59.90% were married couples living together, 3.90% had a female householder with no husband present, and 33.70% were non-families. 30.90% of all households were made up of individuals, and 17.60% had someone living alone who was 65 years of age or older. The average household size was 2.29 and the average family size was 2.87.
The county population contained 23.30% under the age of 18, 5.70% from 18 to 24, 23.50% from 25 to 44, 25.10% from 45 to 64, and 22.40% who were 65 years of age or older. The median age was 44 years. For every 100 females there were 96.90 males. For every 100 females age 18 and over, there were 93.40 males.
The median income for a household in the county was $27,010, and the median income for a family was $35,862. Males had a median income of $22,415 versus $18,583 for females. The per capita income for the county was $15,786. About 11.00% of families and 13.60% of the population were below the poverty line, including 16.10% of those under age 18 and 15.00% of those age 65 or over.
Dundy County voters are reliably Republican. In only three national elections since 1900 has the county selected the Democratic Party candidate (as of 2020).
United States presidential election results for Dundy County, Nebraska[17]
^"Find a County". National Association of Counties. Archived from the original on July 4, 2012. Retrieved June 7, 2011.
^Fitzpatrick, Lilian Linder (1925). Nebraska Place-Names. Lincoln: University of Nebraska Studies in Language, Literature, and Criticism. p. 58. Retrieved December 14, 2014.
^Fitzpatrick, L.L.; Fairclough, G.T. (1960). Nebraska Place-Names. A bison book. University of Nebraska Press. p. 58. ISBN978-0-8032-5060-4. Retrieved May 13, 2019. Dundy county was named in honor of Judge Elmer S. Dundy (1830–1896) of the United States circuit court, a former resident of Falls City, Nebraska. Its boundaries were defined by an act approved February 27, 1873.
^"Dundy County". Nebraska Association of County Officials. Retrieved December 14, 2014.