2020 census As of the
2020 census, there were 8,114 people, 2,376 households, and 1,798 families residing in the city. The median age was 30.4 years. 32.1% of residents were under the age of 18 and 10.1% of residents were 65 years of age or older. For every 100 females there were 88.3 males, and for every 100 females age 18 and over there were 81.9 males age 18 and over. 98.6% of residents lived in urban areas, while 1.4% lived in rural areas. Of the 2,376 households in Los Fresnos, 52.1% had children under the age of 18 living in them. Of all households, 52.1% were married-couple households, 10.9% were households with a male householder and no spouse or partner present, and 31.1% were households with a female householder and no spouse or partner present. About 13.3% of all households were made up of individuals and 7.1% had someone living alone who was 65 years of age or older. There were 2,695 housing units, of which 11.8% were vacant. The homeowner vacancy rate was 2.8% and the rental vacancy rate was 12.2%.
2000 census As of the
census of 2000, 4,512 people, 1,296 households, and 1,092 families resided in the city. The population density was . The 1,480 housing units averaged 613.0 per square mile (237.1/km). The
racial makeup of the city was 81.96% White, 0.42% African American, 0.13% Native American, 0.02% Asian, 0.09% Pacific Islander, 14.38% from other races, and 2.99% from two or more races. Hispanics or Latinos of any race were 84.62% of the population. Of the 1,296 households, 53.5% had children under the age of 18 living with them, 63.7% were married couples living together, 17.7% had a female householder with no husband present, and 15.7% were not families. About 14.2% of all households were made up of individuals, and 7.7% had someone living alone who was 65 years of age or older. The average household size was 3.48, and the average family size was 3.86. In the city, the population was distributed as 36.4% under the age of 18, 9.2% from 18 to 24, 29.2% from 25 to 44, 17.1% from 45 to 64, and 8.1% who were 65 years of age or older. The median age was 28 years. For every 100 females, there were 93.8 males. For every 100 females age 18 and over, there were 84.6 males. The median income for a household in the city was $25,793, and for a family was $27,670. Males had a median income of $20,459 versus $17,904 for females. The
per capita income for the city was $9,507. About 28.5% of families and 34.2% of the population were below the
poverty line, including 43.8% of those under age 18 and 22.4% of those age 65 or over. ==Government and infrastructure==