ZIP Codes in Ontario, CA
Ontario uses 3 ZIP codes, all in San Bernardino County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 3 Ontario ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 91761 | standard | San Bernardino | 62,935 |
| 91762 | standard | San Bernardino | 64,235 |
| 91764 | standard | San Bernardino | 56,270 |
Finding a ZIP+4 in Ontario
Knowing which of these 3 ZIP codes covers an address only gets you partway. The four-digit extension identifies the specific delivery point — typically one side of one block. Two houses facing each other on the same Ontario street almost always have different ZIP+4 codes even though they share all five leading digits.
Appending ZIP+4 to a mailing list?
Upload a CSV of Ontario addresses and download it complete.