In 2022, the population of Leonore was 121, a 0.82% decrease year-by-year from 2021. Previously, in 2021, Leonore's population was 122, a decline of 0.81% compared to a population of 123 in 2020.
The median age in Leonore, IL is 47.2, as per 2021 ACS 5-Year Estimates. Of the total population, 16.30% were under the age of 15, 19.26% aged 15 to 29, 42.22% aged 30 to 64, 10.37% aged 65 to 84, and 11.85% were 85 years of age and older.