Kill Buck is a hamlet in Cattaraugus County, New York, United States.

[3] Kill Buck is roughly evenly divided, with the northern half of the hamlet within the jurisdiction of the town of Great Valley and the southern half within the bounds of the Allegany Indian Reservation; Routes 219 and 417 roughly demarcate the dividing line.

The town of Great Valley maintains a separate fire hall and public park facilities for Kill Buck.

[2] Kill Buck has a post office with ZIP code 14748, which opened on December 28, 1837.

[8] (The proprietor of the store and Kill Buck postmaster since 1975, Bill Costello, had also overseen the closure of the post office in nearby Red House, New York—also inside a Costello-owned store—in the 1960s.)