In 2022, the population of Alsen was 30, a 3.23% decrease year-by-year from 2021. Previously, in 2021, Alsen's population was 31, a decline of 0.00% compared to a population of 31 in 2020.
The median age in Alsen, ND is 35.6, as per 2021 ACS 5-Year Estimates. Of the total population, 22.22% were under the age of 15, 18.52% aged 15 to 29, 37.04% aged 30 to 64, 22.22% aged 65 to 84, and 0.00% were 85 years of age and older.