The following highways are numbered 100B:
New York State Route 100B (NY 100B) is a 2.88-mile (4.63 km) spur route of NY 100 in Westchester County, New York, in the United States. The route follows Dobbs Ferry Road across the southern part of the town of Greenburgh, connecting NY 9A to NY 119. It does not directly connect to NY 100; however, it intersects NY 100A about 1 mile (1.6 km) west of NY 119. NY 100B was assigned in the late 1930s.
