2010 census

As of the census^[12] of 2010, there were 3,603 people, 1,187 households, and 1,007 families living in the town. The population density was 971.2 inhabitants per square mile (375.0/km²). There were 1,234 housing units at an average density of 332.6 per square mile (128.4/km²). The racial makeup of the town was 97.1% White, 0.1% African American, 0.2% Native American, 0.8% Asian, 0.6% from other races, and 1.2% from two or more races. Hispanic or Latino of any race were 1.6% of the population.

There were 1,187 households, of which 48.4% had children under the age of 18 living with them, 73.3% were married couples living together, 7.1% had a female householder with no husband present, 4.5% had a male householder with no wife present, and 15.2% were non-families. 13.1% of all households were made up of individuals, and 5.7% had someone living alone who was 65 years of age or older. The average household size was 3.04 and the average family size was 3.32.

The median age in the town was 38.1 years. 32.3% of residents were under the age of 18; 7.1% were between the ages of 18 and 24; 24% were from 25 to 44; 27.2% were from 45 to 64; and 9.4% were 65 years of age or older. The gender makeup of the town was 49.8% male and 50.2% female.

2000 census

As of the census^[3] of 2000, there were 2,782 people, 922 households, and 778 families living in the town. The population density was 745.1 inhabitants per square mile (287.7/km²). There were 939 housing units at an average density of 251.5 per square mile (97.1/km²). The racial makeup of the town was 97.81% White, 0.07% African American, 0.29% Native American, 0.40% Asian, 0.29% from other races, and 1.15% from two or more races. Hispanic or Latino of any race were 1.04% of the population.

Town and county officials gathered for the incorporation ceremonies of Leo-Cedarville

There were 922 households, out of which 47.3% had children under the age of 18 living with them, 76.2% were married couples living together, 5.7% had a female householder with no husband present, and 15.6% were non-families. 13.0% of all households were made up of individuals, and 5.5% had someone living alone who was 65 years of age or older. The average household size was 3.02 and the average family size was 3.33.

In the town, the population was spread out, with 32.9% under the age of 18, 6.2% from 18 to 24, 32.6% from 25 to 44, 19.9% from 45 to 64, and 8.4% who were 65 years of age or older. The median age was 34 years. For every 100 females, there were 98.0 males. For every 100 females age 18 and over, there were 98.5 males.

The median income for a household in the town was $66,652, and the median income for a family was $70,750. Males had a median income of $48,438 versus $25,552 for females. The per capita income for the town was $22,170. About 1.0% of families and 1.2% of the population were below the poverty line, including none of those under age 18 and 8.6% of those age 65 or over.