Below is a list of Old Westbury NY zip codes. For your research we have also included Old Westbury Area Code, Time Zone, UTC and the local Nassau County FIPS Code. Each Old Westbury New York zip code has a center Longitude / Latitude point (the Old Westbury center is -73.595596313477 / 40.782901763916). For your convenience we have also indicated if that zip code in Old Westbury observes Daylight Savings time.