|• Total||1.98 sq mi (5.13 km2)|
|• Land||1.98 sq mi (5.13 km2)|
|• Water||0 sq mi (0 km2)|
|Elevation||978 ft (298 m)|
|• Estimate (2012)||1,428|
|• Density||728.3/sq mi (281.2/km2)|
|Time zone||Central (CST) (UTC-6)|
|• Summer (DST)||CDT (UTC-5)|
|GNIS feature ID||1564593|
Elroy is located at (43.742016, -90.269597).
As of the census of 2010, there were 1,442 people, 590 households, and 348 families residing in the city. The population density was 728.3 inhabitants per square mile (281.2 /km2). There were 680 housing units at an average density of 343.4 per square mile (132.6 /km2). The racial makeup of the city was 96.8% White, 0.3% African American, 0.8% Native American, 0.2% Asian, 0.3% from other races, and 1.6% from two or more races. Hispanic or Latino of any race were 2.2% of the population.
There were 590 households of which 28.8% had children under the age of 18 living with them, 42.4% were married couples living together, 11.9% had a female householder with no husband present, 4.7% had a male householder with no wife present, and 41.0% were non-families. 33.6% of all households were made up of individuals and 13.4% had someone living alone who was 65 years of age or older. The average household size was 2.32 and the average family size was 2.92.
The median age in the city was 41.6 years. 22.5% of residents were under the age of 18; 6.7% were between the ages of 18 and 24; 24.3% were from 25 to 44; 27% were from 45 to 64; and 19.4% were 65 years of age or older. The gender makeup of the city was 48.2% male and 51.8% female.
As of the census of 2000, there were 1,578 people, 632 households, and 396 families residing in the city. The population density was 823.0 people per square mile (317.3/km²). There were 692 housing units at an average density of 360.9 per square mile (139.2/km²). The racial makeup of the city was 98.48% White, 0.32% African American, 0.32% Native American, 0.13% Asian, 0.38% from other races, and 0.38% from two or more races. Hispanic or Latino of any race were 1.27% of the population.
There were 632 households out of which 31.5% had children under the age of 18 living with them, 48.7% were married couples living together, 9.5% had a female householder with no husband present, and 37.3% were non-families. 32.0% of all households were made up of individuals and 15.0% had someone living alone who was 65 years of age or older. The average household size was 2.36 and the average family size was 2.97.
In the city the population was spread out with 26.0% under the age of 18, 7.7% from 18 to 24, 26.7% from 25 to 44, 19.4% from 45 to 64, and 20.2% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 95.3 males. For every 100 females age 18 and over, there were 88.1 males.
The median income for a household in the city was $31,859, and the median income for a family was $42,452. Males had a median income of $31,699 versus $24,250 for females. The per capita income for the city was $15,529. About 9.9% of families and 14.2% of the population were below the poverty line, including 17.3% of those under age 18 and 11.8% of those age 65 or over.
Elroy was for many years an important railroad hub in the area. The Baraboo Air Line reached Elroy in the 1870s. The Air Line was later acquired by the Chicago and North Western Railway and the line was pushed on to Sparta, Wisconsin. It eventually became the main line of the CNW between Chicago, Illinois and Minneapolis, Minnesota. The Chicago, St. Paul, Minneapolis and Omaha Railway also became a presence in Elroy when its line was built south from Camp Douglas, Wisconsin. Both railroad companies kept roundhouses and other operations in Elroy. Rail traffic on the Elroy portion of the CNW eventually declined, due to the construction of better mainline trackage further to the north (via Adams, Necedah, and Wyeville). The rails on this portion were taken up in the mid-1960s and the right-of-way was converted into the Elroy-Sparta Bike Trail, as it remains today. The CNW tracks from Elroy southeast to Reedsburg, Wisconsin, along with those of the north-south Omaha line, were taken up in the 1990s, and these rights-of-way are now known as the "400" State Trail, and the Omaha Trail, respectively.
- Tommy Thompson was an Elroy resident. A Republican, he was the Governor of Wisconsin for four terms and the United States Secretary of Health and Human Services during the first term of George W. Bush. He was a Republican candidate for the 2008 United States presidential election.
- Governor Thompson's brother Ed Thompson ran unsuccessfully for Wisconsin governor on the Libertarian ticket in 2002.
- Larry Ormson and Northern Plastics produced the game Trivial Pursuit in Elroy; 30,000,000 games from 1983-1985.
- Tim Brady, author of the book The Great Dan Patch and the Remarkable Mr. Savage, was formerly a resident of Elroy. He now lives in St. Paul, Minnesota.
- Navy Cross recipient Conrad Shaker was born in Elroy.
- Navy Cross recipient Wallace Brady lived in Elroy.
- Columnist Peter Egan was born in Elroy.
- Author Daniyal Mueenuddin lived part-time on a farm outside Elroy.
- "US Gazetteer files 2010". United States Census Bureau. Retrieved 2012-11-18.
- "US Board on Geographic Names". United States Geological Survey. 2007-10-25. Retrieved 2008-01-31.
- "American FactFinder". United States Census Bureau. Retrieved 2012-11-18.
- "Population Estimates". United States Census Bureau. Retrieved 2013-06-24.
- "American FactFinder". United States Census Bureau. Retrieved 2008-01-31.
- "US Gazetteer files: 2010, 2000, and 1990". United States Census Bureau. 2011-02-12. Retrieved 2011-04-23.