2020 census
As of the 2020 census, O'Donnell had 704 people, 285 households, and 252 families residing in the city, and the median age was 39.4 years. [11]
26.3% of residents were under the age of 18 and 18.8% of residents were 65 years of age or older. For every 100 females there were 97.8 males, and for every 100 females age 18 and over there were 98.9 males age 18 and over. [11]
0.0% of residents lived in urban areas, while 100.0% lived in rural areas. [12]
Of the 285 households in O'Donnell, 39.6% had children under the age of 18 living in them, 47.0% were married-couple households, 18.9% were households with a male householder and no spouse or partner present, and 25.3% were households with a female householder and no spouse or partner present. About 21.4% of all households were made up of individuals and 11.9% had someone living alone who was 65 years of age or older. [11]
There were 338 housing units, of which 15.7% were vacant. The homeowner vacancy rate was 0.0% and the rental vacancy rate was 8.4%. [11]
2010 census
As of the 2010 United States census, O'Donnell had 831 people, a 17.8% reduction from the 2000 US Census. [14] The population resided in 315 households, of which 237 were identified as family households. The racial makeup of the city was 73.4% White, 1.2% African American, 0.6% Native American, 0.4% Asian, 20.3% from other races, and 4.1% from two or more races. Hispanics or Latinos of any race were 62.8% of the population. [14]
In the city, the age distribution was 31.2% under 18, 52.0% from 18 to 64, and 16.8% who were 65 or older. The median age was 38.5 years. [14]
The median income for a household in the city was $26,103, and for a family was $30,833. Males had a median income of $26,193 versus $15,917 for females. The per capita income for the city was $12,924. About 24.4% of families and 24.8% of the population were below the poverty line, including 31.1% of those under age 18 and 15.0% of those age 65 or over.
United States 
Texas 
