Edinburg is a city in and the county seat of Hidalgo County, Texas, United States. The population was 100,243 at the 2020 census, and in 2022…Edinburg is a city in and the county seat of Hidalgo County, Texas, United States. The population was 100,243 at the 2020 census, and in 2022, its estimated population was 104,294, making it the second-largest city in Hidalgo County, and the third-largest city in the larger Rio Grande Valley region.