In 2022, the population of Glenham was 108, a 0.93% increase year-by-year from 2021. Previously, in 2021, Glenham's population was 107, a decline of 1.83% compared to a population of 109 in 2020.
The median age in Glenham, SD is 60.3, as per 2021 ACS 5-Year Estimates. Of the total population, 4.17% were under the age of 15, 8.33% aged 15 to 29, 53.33% aged 30 to 64, 26.67% aged 65 to 84, and 7.50% were 85 years of age and older.