Banner County is part of the Scottsbluff, Nebraska Micropolitan Statistical Area.
In the Nebraska license plate system, Banner County is represented by the prefix 85 (it had the eighty-fifth-largest number of vehicles registered in the county when the license plate system was established in 1922).
1890 - 2,435 1900 - 1,114 1910 - 1,444 1920 - 1,435 1930 - 1,676 1940 - 1,403 1950 - 1,325 1960 - 1,269 1970 - 1,034 1980 - 918 1990 - 852 2000 - 819
As of the census of 2000, there were 819 people, 311 households, and 237 families residing in the county. The population density was 1 people per square mile (0.42/km²). There were 375 housing units at an average density of 0 per square mile (0/km²). The racial makeup of the county was 95.85% White, 0.12% Black or African American, 0.24% Native American, 0.12% Asian, 3.05% from other races, and 0.61% from two or more races. 5.62% of the population were Hispanic or Latino of any race. 31.2% were of German, 14.4% English, 14.1% American, 8.0% Swedish, 6.8% Irish and 5.0% Norwegian ancestry according to Census 2000.
There were 311 households out of which 30.20% had children under the age of 18 living with them, 70.10% were married couples living together, 4.20% had a female householder with no husband present, and 23.50% were non-families. 19.90% of all households were made up of individuals and 9.60% had someone living alone who was 65 years of age or older. The average household size was 2.63 and the average family size was 3.06.
In the county the population was spread out with 28.80% under the age of 18, 3.70% from 18 to 24, 24.30% from 25 to 44, 27.20% from 45 to 64, and 16.00% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 108.40 males. For every 100 females age 18 and over, there were 101.00 males.
The median income for a household in the county was $31,339, and the median income for a family was $41,538. Males had a median income of $25,250 versus $18,750 for females. The per capita income for the county was $17,149. About 12.30% of families and 13.60% of the population were below the poverty line, including 19.00% of those under age 18 and 11.10% of those age 65 or over.