11788 -- U.S. ZIP code Municipality (1990): HAUPPAUGE, New York All ZIPs for this municipality (1990): 11788 Population (2000): 16836 Housing Units (2000): 5919 Land area (2000): 9.302547 sq. miles (24.093484 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 9.302547 sq. miles (24.093484 sq. km) Located within: New York (NY) Location: 40.819266 N, 73.209674 W