As another post office named Waverly already existed in Upstate New York, the name of the hamlet was changed to Holtsville in 1860, in honor of U.S. Postmaster General Joseph Holt.
The communities included in the 7th Legislative District include Blue Point, Patchogue, East Patchogue, North Patchogue, most of Medford, and smaller portions of Coram, Farmingville, Holtsville, Ronkonkoma, Bellport, and Fire Island.