The town of Bourne is divided into two sections by the Cape Cod Canal, with Wareham and Plymouth along its northern border and Falmouth to the south.

In total, Bourne is 41 square miles in size, and 83% of the town is located within the Buzzards Bay watershed. Bourne’s 66 miles of coastline extend south from Buttermilk Bay along Buzzards Bay’s eastern shore to Megansett Harbor.