The population in 1980 was 2,574, an increase of 60.6% since 1970. In 1990, the population was 3,508, and the city's population in 2010 was 6,916. As of the 2020 United States census, 8,839 people, 2,842 households, and 2,055 families resided in the city.
Note: NH = Non-Hispanic. 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.
Public education in Sanger is run under the Sanger Independent School District, an independent government. The superintendent of the Sanger public schools is Dr. Sandra McCoy-Jackson. Eight different schools are in Sanger, Texas: Sanger High School, Linda Tutt High School, Sanger Middle School, Sanger 6th Grade Campus, Clear Creek Intermediate School, Butterfield Elementary School, Chisholm Trail Elementary, and Tenderfoot Child Development Center. The new facilities in the Sanger Independent School district are one of the high schools and the new elementary school. The City of Sanger considers the school district a partner of the cities and they work very closely with one another. Sanger ISD has recently introduced a district wide initiative to integrate instructional technology with effective teaching practices. They currently have a 1:1 student technology lending program for grades 8–12 and have increased available technology in all grades across the district.