In 2022, the population of Merwin was 68, a 1.49% increase year-by-year from 2021. Previously, in 2021, Merwin's population was 67, a decline of 0.00% compared to a population of 67 in 2020.
The median age in Merwin, MO is 48.3, as per 2021 ACS 5-Year Estimates. Of the total population, 0.00% were under the age of 15, 40.38% aged 15 to 29, 50.00% aged 30 to 64, 9.62% aged 65 to 84, and 0.00% were 85 years of age and older.