View source for Colwell, Iowa

===2020 census===
As of the [[United States census|census]] of 2020,<ref>{{cite web |title=2020 Census |url=https://www.census.gov/programs-surveys/decennial-census/decade/2020/2020-census-main.html |publisher=United States Census Bureau}}</ref> there were 55 people, 24 households, and 20 families residing in the city. The [[population density]] was 333.2 inhabitants per square mile (128.7/km<sup>2</sup>). There were 25 housing units at an average density of 151.5 per square mile (58.5/km<sup>2</sup>). The [[Race and ethnicity in the United States census|racial]] makeup of the city was 100.0% [[White Americans|White]], 0.0% [[African Americans|Black or African American]], 0.0% [[Native Americans in the United States|Native American]], 0.0% [[Asian Americans|Asian]], 0.0% [[Pacific Islander Americans|Pacific Islander]], 0.0% from other races and 0.0% from two or more races. [[Hispanic and Latino Americans|Hispanic or Latino]] persons of any race comprised 0.0% of the population.

Of the 24 households, 41.7% of which had children under the age of 18 living with them, 50.0% were [[Marriage|married couples]] living together, 4.2% were cohabitating couples, 16.7% had a female householder with no spouse or partner present and 29.2% had a male householder with no spouse or partner present. 16.7% of all households were non-families. 0.0% of all households were made up of individuals, 0.0% had someone living alone who was 65 years old or older.

The median age in the city was 42.8 years. 23.6% of the residents were under the age of 20; 0.0% were between the ages of 20 and 24; 29.1% were from 25 and 44; 32.7% were from 45 and 64; and 14.5% were 65 years of age or older. The gender makeup of the city was 49.1% male and 50.9% female.