Gilmer is a city in and the county seat of Upshur County, Texas, United States. The population was 4,799 at the 2000 census.
Gilmer is located at 32°43'57" North, 94°56'49" West (32.732387, -94.946980).
According to the United States Census Bureau, the city has a total area of 4.6 square miles (12.0 km²), all of it land.
Four miles west of Gilmer is Lake Gilmer, which opened September 29, 2001.
There were 1,926 households out of which 30.1% had children under the age of 18 living with them, 46.2% were married couples living together, 17.7% had a female householder with no husband present, and 32.5% were non-families. 29.9% of all households were made up of individuals and 17.3% had someone living alone who was 65 years of age or older. The average household size was 2.37 and the average family size was 2.93.
In the city the population was spread out with 25.3% under the age of 18, 7.8% from 18 to 24, 23.5% from 25 to 44, 21.6% from 45 to 64, and 21.8% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 83.4 males. For every 100 females age 18 and over, there were 76.3 males.
The median income for a household in the city was $28,487, and the median income for a family was $39,688. Males had a median income of $32,437 versus $17,910 for females. The per capita income for the city was $16,823. About 15.9% of families and 19.1% of the population were below the poverty line, including 26.5% of those under the age of 18 and 21.0% of those 65 and older.