St. Mary township is located in McLean County, North Dakota. St. Mary township has a 2026 population of 208. St. Mary township is currently growing at a rate of 0.97% annually and its population has increased by 4.52% since the most recent census, which recorded a population of 199 in 2020.
The median age in St. Mary township is 73 years: 73.4 years for males, and 72 years for females. For every 100 females there are 166.7 males.
Data after 2023 is projected based on recent change
Overall: 73 years
Female: 72 years
Male: 73.4 years
There are 168 adults, (168 of whom are seniors) in St. Mary township.
Female: 63 (37.5%)
Male: 105 (62.5%)
The racial composition of St. Mary township includes 94.05% White, and smaller percentages for and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 158 | 94.05% |
| Two or more races | 10 | 5.95% |