Belle Chasse is located at 29°51'16" North, 89°59'25" West (29.854722, -89.990278).
According to the United States Census Bureau, the city has a total area of 28.44 mi2 (73.65 km2). 25.02 mi2 (64.81 km2) of it is land and 3.41 mi2 (8.84 km2) of it is covered by water. The total area is 12.00% water.
Belle Chasse is located in the Central Standard Time (CST) timezone, GMT-06:00. It observes Daylight Saving Time (DST).