According to the U.S. Census Bureau, Palmyra has a total area of , all land. Solomon Creek, part of the Macoupin Creek watershed leading to the Illinois River, flows southward along the western border of the village.
According to the U.S. Census Bureau, Palmyra has a total area of  all land. Solomon Creek, part of, the Macoupin Creek watershed leading to the Illinois River, flows southward along the western border of the village.