Mission is located in Hidalgo County, Texas. The population was 77,058 at the 2010 census. Mission is part of the McAllen–Edinburg–Mission and Reynosa–McAllen metropolitan areas.

The median income for a household in the city was $30,647, and the median income for a family was $33,465. Males had a median income of $25,710 versus $20,718 for females. The per capita income for the city was $12,796. About 22.6% of families and 26.8% of the population were below the poverty line, including 37.4% of those under age 18 and 15.6% of those age 65 or over.