Diamond Bar, CA ZIP Codes
Diamond Bar, California has 2 ZIP codes: 2 for street addresses ( and ).
Your street decides which one you use.
Which Diamond Bar ZIP code is my address in?
Street ranges from the Census Bureau, 2026. PO box and organization ZIP codes are not found by street. A new street may be missing: address not found?
Diamond Bar ZIP code map
Tap or point to an area to see its ZIP code.Full-size map
Dashed line: Diamond Bar city limits.
Map: Census Bureau ZIP Code Tabulation Areas (2020) and place limits (2024).
All Diamond Bar ZIP codes by type
| ZIP | Type and post office or station |
|---|---|
| 91765 | street delivery Diamond Bar |
| 91789 | street delivery; mail may be addressed to Walnut Walnut |
Why your mail may say Diamond Bar when you live outside it
Diamond Bar ZIP codes also cover Walnut and Industry, so a letter addressed to Diamond Bar can go to a home outside the city limits.
A ZIP code does not set your city, school district or tax. Los Angeles County property records show which city you are in.
Diamond Bar ZIP code questions
What is the main ZIP code for Diamond Bar?
91765, the ZIP code of the main Diamond Bar post office at 1317 S Diamond Bar Blvd.
What county is Diamond Bar in?
Los Angeles County.
ZIP codes for towns near Diamond Bar
More towns near Diamond Bar: San Dimas, La Puente, Yorba Linda, Montclair, Chino, Placentia, La Verne, Hacienda Heights, La Habra.
Sources and last checked
USPS ZIP Locale Detail (October 1, 2026), GeoNames (CC BY 4.0), U.S. Census Bureau, HUD-USPS crosswalk.
Checked October 20, 2026. Sources · How we build our lists · Corrections