14221 -- U.S. ZIP code Municipality (1990): WILLIAMSVILLE, New York All ZIPs for this municipality (1990): 14221 Population (2000): 51448 Housing Units (2000): 21530 Land area (2000): 22.826359 sq. miles (59.119996 sq. km) Water area (2000): 0.010372 sq. miles (0.026863 sq. km) Total area (2000): 22.836731 sq. miles (59.146859 sq. km) Located within: New York (NY) Location: 42.977456 N, 78.733561 W