In 2022, the population of Mize was 312, a 0.64% decrease year-by-year from 2021. Previously, in 2021, Mize's population was 314, a decline of 0.00% compared to a population of 314 in 2020.
The median age in Mize, MS is 34.8, as per 2021 ACS 5-Year Estimates. Of the total population, 32.87% were under the age of 15, 11.52% aged 15 to 29, 39.89% aged 30 to 64, 13.48% aged 65 to 84, and 2.25% were 85 years of age and older.