Hillsdale is a village in Rock Island County, Illinois, United States. The population was 523 at the 2010 census.
Hillsdale is located at 41°36′37″N 90°10′25″W / 41.61028°N 90.17361°W / 41.61028; -90.17361 (41.610304, -90.173573).
According to the 2010 census, Hillsdale has a total area of 0.779 square miles (2.02 km), of which 0.75 square miles (1.94 km) (or 96.28%) is land and 0.029 square miles (0.08 km) (or 3.72%) is water.
As of the census of 2000, there were 588 people, 219 households, and 157 families residing in the village. The population density was 780.2 people per square mile (302.7/km²). There were 237 housing units at an average density of 314.5 per square mile (122.0/km²). The racial makeup of the village was 95.75% White, 0.51% African American, 0.68% Native American, 1.70% from other races, and 1.36% from two or more races. Hispanic or Latino of any race were 2.72% of the population.
There were 219 households out of which 35.6% had children under the age of 18 living with them, 52.5% were married couples living together, 14.6% had a female householder with no husband present, and 28.3% were non-families. 21.9% of all households were made up of individuals and 4.1% had someone living alone who was 65 years of age or older. The average household size was 2.68 and the average family size was 3.13.
In the village, the population was spread out with 28.7% under the age of 18, 8.2% from 18 to 24, 31.8% from 25 to 44, 21.8% from 45 to 64, and 9.5% who were 65 years of age or older. The median age was 34 years. For every 100 females, there were 89.1 males. For every 100 females age 18 and over, there were 94.0 males.
The median income for a household in the village was $46,964, and the median income for a family was $49,519. Males had a median income of $31,250 versus $20,313 for females. The per capita income for the village was $21,772. About 9.2% of families and 11.0% of the population were below the poverty line, including 15.2% of those under age 18 and none of those age 65 or over.