Jack's Reef is a hamlet in the Town of Van Buren, New York in Onondaga County, New York. It was developed around an inn, extant today as a restaurant, where Old Route 31 (supplanted by modern NY Route 31) bent around a large oxbow in the Seneca River. Subsequently a canal was cut about a mile to the north, which shortened the navigation route. Consequently, Jack's Reef lost virtually all commercial and much recreational traffic. The nearby Seneca River still attracted summer residents, however. Today year-round homes are being built nearby, as the hamlet is within commuting range of Syracuse, New York.