According to the U.S. Census Bureau, the county has a total area of 628 square miles (1,630 km2), of which 569 square miles (1,470 km2) are land and 59 square miles (150 km2) (9.3%) are covered by water.[3]
U.S. Decennial Census[5] 1850–2010[6] 2010[7] 2020[8]
San Jacinto County, Texas – Racial and ethnic composition Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race.
As of the census[10] of 2000, there were 22,246 people, 8,651 households, and 6,401 families residing in the county. The population density was 39 people per square mile (15 people/km2). There were 11,520 housing units at an average density of 20 units per square mile (7.7/km2). The racial makeup of the county was 83.64% White, 12.64% Black or African American, 0.46% Native American, 0.28% Asian, 0.07% Pacific Islander, 1.63% from other races, and 1.28% from two or more races. 4.87% of the population were Hispanic or Latino of any race.
There were 8,651 households, out of which 30.00% had children under the age of 18 living with them, 60.20% were married couples living together, 9.70% had a female householder with no husband present, and 26.00% were non-families. 22.60% of all households were made up of individuals, and 10.10% had someone living alone who was 65 years of age or older. The average household size was 2.55 and the average family size was 2.98.
In the county, the population was spread out, with 25.20% under the age of 18, 7.40% from 18 to 24, 24.90% from 25 to 44, 26.60% from 45 to 64, and 15.90% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 100.50 males. For every 100 females age 18 and over, there were 97.40 males.
The median income for a household in the county was $32,220, and the median income for a family was $37,781. Males had a median income of $34,614 versus $22,313 for females. The per capita income for the county was $16,144. About 15.10% of families and 18.80% of the population were below the poverty line, including 22.80% of those under age 18 and 17.60% of those age 65 or over.
Areas of San Jacinto County in Coldspring-Oakhurst CISD and Shepherd ISD are assigned to Angelina College. Areas in Cleveland ISD and Willis ISD are assigned to Lone Star College.[12]