Gilbertown is located in southern Choctaw County at 31°52'36.034" North, 88°19'15.265" West (31.876676, -88.320907).
According to the U.S. Census Bureau, the town has a total area of 0.77 square miles (2.0 km2), all of it land.
The first permit to drill an oil well in Alabama, the A. R. Jackson Well No. 1, was granted to the Hunt Oil Company on January 2, 1944, near Gilbertown. Drilling started January 10, 1944, and struck in chalk of the Selma Group approximately one month later at a depth of 2,580 feet (790 m).