- Southern Terminus:
- Merrick Road (Nassau CR 27) in Massapequa
- Northern Terminus:
- Pratt Boulevard (Nassau CR 243) and Pulaski Street in Glen Cove
- 17.18 miles
NY 107 begins as Hicksville Road at Merrick Road (CR 27) in Massapequa. It runs to the northwest from there. In the vicinity of Hicksville, it changes name to become Broadway. Just north of Old Country Road (CR 25), it merges with NY 106 and the two are multiplexed along Broadway. There are major intersections with the Northern Parkway, the Long Island Expressway (I-495), and Jericho Turnpike (NY 25). Just north of Jericho Turnpike (NY 25), NY 106 and NY 107 split and NY 107 runs to the northwest as Cedar Swamp Road. North of Northern Boulevard (NY 25A), Cedar Swamp Road merges into Glen Cove Road and NY 107 continues north on Glen Cove Road. At Pulaski Street in Glen Cove, Glen Cove Road becomes Pratt Boulevard (CR 243). NY 107 ends at this point. Pratt Boulevard continues for another two blocks to end at Glen Cove Avenue.