As of the 2020 census, Great Notch had a population of 3,289. The median age was 47.5 years. 15.4% of residents were under the age of 18 and 24.3% of residents were 65 years of age or older. For every 100 females there were 88.5 males, and for every 100 females age 18 and over there were 85.3 males age 18 and over.^[10][11]

100.0% of residents lived in urban areas, while 0.0% lived in rural areas.^[12]

There were 1,399 households in Great Notch, of which 23.4% had children under the age of 18 living in them. Of all households, 52.1% were married-couple households, 13.5% were households with a male householder and no spouse or partner present, and 29.6% were households with a female householder and no spouse or partner present. About 30.1% of all households were made up of individuals and 13.1% had someone living alone who was 65 years of age or older.^[10]

There were 1,481 housing units, of which 5.5% were vacant. The homeowner vacancy rate was 1.2% and the rental vacancy rate was 8.7%.^[10][11]