Geronimo is an unincorporated community and census-designated place (CDP) in Guadalupe County, Texas, United States. The population was 1,032 at the 2010 census, up from 619 at the 2000 census. It is part of the San Antonio Metropolitan Statistical Area.

Guadalupe County is a county located in the U.S. state of Texas. As of the 2020 census, its population was 172,706. The county seat is Seguin. The county was founded in 1846 and is named after Guadalupe River.