ZIP Code 94523 — Pleasant Hill, CA
94523 is a standard (street delivery) ZIP code serving Pleasant Hill, California, in Contra Costa County. To mail something here you only need these five digits — but the four-digit extension narrows delivery to a single point, and it is what USPS bulk postage discounts are priced on.
ZIP code 94523 at a glance
| ZIP code | 94523 |
|---|---|
| Primary city | Pleasant Hill |
| State | California (CA) |
| County | Contra Costa FIPS 06013 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 34,592 |
| Coordinates | 37.954030, -122.076080 |
How ZIP+4 works in 94523
The four digits after the hyphen encode a delivery segment inside 94523. In practice one segment usually means:
- One side of one block — odd numbers on a street between two cross streets
- A single large building, or one floor of it
- A group of PO boxes, sometimes a single box
- A single business that receives enough mail to warrant its own code
That is why 94523 has no single ZIP+4: two neighbors across the street from each other usually have different ones. Enter a street address above and we will return the exact nine-digit code along with the standardized USPS address format.
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 94523.
| ZIP | City | Distance |
|---|---|---|
| 94597 | Walnut Creek, CA | 2.5 mi |
| 94518 | Concord, CA | 2.9 mi |
| 94520 | Concord, CA | 3.5 mi |
| 94519 | Concord, CA | 4.2 mi |
| 94549 | Lafayette, CA | 4.3 mi |
| 94553 | Martinez, CA | 4.6 mi |
| 94596 | Walnut Creek, CA | 5 mi |
| 94595 | Walnut Creek, CA | 5.7 mi |
| 94521 | Concord, CA | 5.8 mi |
| 94598 | Walnut Creek, CA | 6.6 mi |
| 94507 | Alamo, CA | 7.9 mi |
| 94575 | Moraga, CA | 7.9 mi |
Questions about 94523
What is the ZIP+4 code for 94523?
94523 is the five-digit ZIP code. The ZIP+4 adds four more digits that identify a specific delivery point — usually one side of a city block, a single building, or a group of PO boxes. Because those four digits change from address to address within 94523, you need to look up a specific street address to get them.
What city is 94523?
94523 is assigned to Pleasant Hill, California, in Contra Costa County.
Do I need to use the ZIP+4?
It is optional for ordinary mail, but it speeds up sorting and it is required for most USPS bulk-mail postage discounts. Many address-verification and e-commerce systems also use ZIP+4 to confirm a delivery point exists.
Need thousands of these?
Upload a CSV and get ZIP+4, county, carrier route, and delivery-point data appended to every row — or call the API directly.