The total population of Mill Creek is estimated to be 45 with 24 males (53.33%) and 21 females (46.67%). There are 3 less females than males in Mill Creek.
In 2022, the population of Mill Creek was 55, a 1.79% decrease year-by-year from 2021. Previously, in 2021, Mill Creek's population was 56, a decline of 1.75% compared to a population of 57 in 2020.
The median age in Mill Creek, IL is 37.5, as per 2021 ACS 5-Year Estimates. Of the total population, 6.45% were under the age of 15, 41.94% aged 15 to 29, 41.94% aged 30 to 64, 9.68% aged 65 to 84, and 0.00% were 85 years of age and older.