Ottawa is a medium-sized city located in the state of Illinois. With a population of 18,775 people and five associated neighborhoods, Ottawa is the 132nd largest community in Illinois.

The population of Ottawa overall has a level of education that is slightly above the US average for all US cities and towns of 21.84%. Of adults 25 and older in Ottawa, 23.26% have at least a bachelor's degree.

The per capita income in Ottawa in 2022 was $40,071, which is upper middle income relative to Illinois and the nation. This equates to an annual income of $160,284 for a family of four. However, Ottawa contains both very wealthy and poor people as well.

Ottawa is a somewhat ethnically-diverse city. The people who call Ottawa home describe themselves as belonging to a variety of racial and ethnic groups. The greatest number of Ottawa residents report their race to be White, followed by Black or African-American. Ottawa also has a sizeable Hispanic population (people of Hispanic origin can be of any race). People of Hispanic or Latino origin account for 10.09% of the city’s residents. Important ancestries of people in Ottawa include German, Irish, English, Polish, and Italian.

The most common language spoken in Ottawa is English. Other important languages spoken here include Spanish and German/Yiddish.