The median age in Grimstad Township, Minnesota is 54.5, as per 2021 ACS 5-Year Estimates. Of the total population, 8.82% were under the age of 15, 2.94% aged 15 to 29, 65.69% aged 30 to 64, 22.55% aged 65 to 84, and 0.00% were 85 years of age and older.