Wallkill is a hamlet (and census-designated place), generally identified as coterminous with ZIP code 12589, telephone exchange 895 in the 845 area code and most of the Wallkill Central School District located mostly in the eastern half of the Town of Shawangunk, Ulster County, New York but partly spilling over into adjacent regions of the Orange County towns of Newburgh and Montgomery. The population was 2,288 at the 2010 census.
The community is in the Town of Shawangunk. Residents affectionately refer to the town by its unofficial nickname "The Kill". The Wallkill Correctional Facility and Shawangunk Correctional Facility are located in Wallkill. The hamlet's attractions include the Walden–Wallkill Rail Trail, the Original Borden Farm (namesake for the area's middle school), the Wallkill River, the Magnanini Winery, and for its proximity to the Shawangunk Mountains.
Wallkill is also a destination for international visitors to Watchtower Farms, which draws tens of thousands each year to a free guided tour of its printery. The Watchtower Society (a legal entity of Jehovah's Witnesses) has operated the facility since 1963, initially to produce food cost-effectively for volunteer workers at its offices and printeries in Brooklyn, New York. Some printing of Awake! and The Watchtower began at Wallkill in 1973, and by 2004 their entire United States printing operation was shifted from Brooklyn to an expanded Wallkill printery. The Watchtower printery at Wallkill is considered an example in automated printing, binding, and packaging. Aside from those run for the federal government, Watchtower's Wallkill plant is the largest in-plant printing operation in the United States.