Fulton is located at 28°3'39" North, 97°2'26" West (28.061111, -97.040556).
According to the United States Census Bureau, the town has a total area of 2.19 mi2 (5.68 km2). 1.35 mi2 (3.50 km2) of it is land and 0.84 mi2 (2.18 km2) of it is covered by water. The total area is 38.39% water.
Fulton is located in the Central Standard Time (CST) timezone, GMT-06:00. It observes Daylight Saving Time (DST).