Post office locations in 11788
| Post Office | Address | Phone | Hours |
| HAUPPAUGE | 960 WHEELER RD HAUPPAUGE, NY 11788 - 2847 | 631-360-7229 | Mon-Fri 9:00am - 5:00pm Sat 9:00am - 12:00pm Sun Closed |
| HAUPPAUGE INDUSTRIAL PARK | 150 OSER AVE HAUPPAUGE, NY 11788 - 3711 | 631-231-3155 | Mon-Fri 9:00am - 5:00pm Sat-Sun Closed |