Avinger is located in southwestern Cass County. Texas State Highway 49 passes through the town center, leading northwest 9 miles (14 km) to Hughes Springs and southeast 16 miles (26 km) to Jefferson. Texas State Highway 155 crosses Highway 49 southeast of the town center and leads northeast 14 miles (23 km) to Linden, the Cass County seat, and southwest 27 miles (43 km) to Gilmer.
According to the United States Census Bureau, Avinger has a total area of 2.0 square miles (5.1 km2), of which 0.01 square miles (0.03 km2), or 0.56%, is water.[4]
As of the 2020 United States census, there were 371 people, 123 households, and 64 families residing in the town.
At the publication of the 2000 United States census, there were 464 people, 203 households, and 132 families residing in the town.[3] The population density was 248.2 inhabitants per square mile (95.8/km2). There were 236 housing units at an average density of 126.3 per square mile (48.8/km2). The racial makeup of the town was 75.43% White, 22.63% African American, 0.43% from other races, and 1.51% from two or more races. Hispanic or Latino of any race were 1.94% of the population.
^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 can be of any race.[9]