Racial and ethnic composition 2020 census As of the
2020 census, Monticello had a population of 2,589. The median age was 48.5 years. 19.0% of residents were under the age of 18 and 25.8% of residents were 65 years of age or older. For every 100 females there were 86.4 males, and for every 100 females age 18 and over there were 81.2 males age 18 and over. 0.0% of residents lived in urban areas, while 100.0% lived in rural areas. There were 1,114 households in Monticello, of which 25.6% had children under the age of 18 living in them. Of all households, 33.7% were married-couple households, 19.7% were households with a male householder and no spouse or partner present, and 41.9% were households with a female householder and no spouse or partner present. About 35.8% of all households were made up of individuals and 17.3% had someone living alone who was 65 years of age or older. In the 2020 ACS, there were 711 families residing in the city.
2010 census As of the
2010 United States census, there were 2,506 people, 770 households, and 559 families residing in the city. ==Notable people==