Below is a list of San Diego TX zip codes. For your research we have also included San Diego Area Code, Time Zone, UTC and the local Duval County FIPS Code. Each San Diego Texas zip code has a center Longitude / Latitude point (the San Diego center is -98.239799499512 / 27.761299133301). For your convenience we have also indicated if that zip code in San Diego observes Daylight Savings time.