In 2022, the population of Leslie was 140, a 1.45% increase year-by-year from 2021. Previously, in 2021, Leslie's population was 138, a decline of 0.72% compared to a population of 139 in 2020.
The median age in Leslie, MO is 38.7, as per 2021 ACS 5-Year Estimates. Of the total population, 26.76% were under the age of 15, 8.45% aged 15 to 29, 57.75% aged 30 to 64, 7.04% aged 65 to 84, and 0.00% were 85 years of age and older.