According to the United States Census Bureau, the city has a total area of 7.3 square miles (19.0 km²), of which, 7.3 square miles (18.8 km²) of it is land and 0.1 square miles (0.1 km²) of it (0.68%) is water.
There were 2,919 households out of which 37.2% had children under the age of 18 living with them, 48.6% were married couples living together, 12.1% had a female householder with no husband present, and 34.8% were non-families. 28.5% of all households were made up of individuals and 11.2% had someone living alone who was 65 years of age or older. The average household size was 2.48 and the average family size was 3.07.
In the city the population was spread out with 28.0% under the age of 18, 8.7% from 18 to 24, 32.2% from 25 to 44, 18.3% from 45 to 64, and 12.8% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 91.4 males. For every 100 females age 18 and over, there were 87.5 males.
The median income for a household in the city was $38,395, and the median income for a family was $47,475. Males had a median income of $34,867 versus $22,253 for females. The per capita income for the city was $20,003. About 7.4% of families and 9.9% of the population were below the poverty line, including 12.7% of those under age 18 and 10.1% of those age 65 or over.
The area's beauty and fertile soil lead Daniel Bradley, his brother Milo, and LeGrand Rockwell to create a village in the area. The success of the village lead to the first town meeting held in 1846. The growth of the city had reached 539 people the year of the first town meeting. Elkhorn was designated county seat that same year because of its position in Walworth County.
In 1851, Elkhorn became the residence of the Walworth County Fair. The fair has been ranked as one of the greatest fairs in the country. The event has been bringing people from all around the country since its birth.
Elkhorn has been known as the nation's 'Christmas Card Town' since the city has been places unique Christmas decorations around its center since before World War II. This tradition of being the 'Christmas Card Town is celebrated and noted every year with the oil paintings done by local artist Jan Castle Reed. This tradition of a new painting every year came from the 1950's watercolor paintings done for the Ford Motor Company. These watercolor paintings were turned into Christmas cards and sent all around the country.
Today, Elkhorn still continues to keep its small town Christmas feeling by not allowing big box stores to come in and drive out small business. Small businesses actually can get grants to influence growth in Elkhorn.