Wappingers Falls is located in Dutchess County, NY, near the Hudson River.

According to local legend, New York City merchants Francis Rombout and Gulian Verplanck bought land from the Wappinger Indians. Rombout bargained for "all the land he could see," then climbed to the top of Mount Beacon. His land grant included what is now the city of Beacon and the towns of Wappinger, Fishkill and East Fishkill.
 
One half (closer to 2/3) of the Village of Wappingers Falls is located within the Town of Wappinger. However the large post office which services both municipalities is located in the Village of Wappingers Falls. Thus both the Village of Wappingers Falls and the Town of Wappinger (as well as portions of Fishkill, East Fishkill, Poughkeepsie and Lagrange) all have the same zip code; WAPPINGERS FALLS, NY 12590. This often results in confusion. The Town of Wappinger is 28 square miles (73 km²). Truckers and travelers often attempt to locate an address in the 1.2-square-mile (3.1 km²) Village of Wappingers Falls when the location they are actually seeking is somewhere in the much larger Town of Wappinger (or portions of Fishkill, East Fishkill, Poughkeepsie and Lagrange).