ZIP Code 94505 — Discovery Bay, CA
94505 is a standard (street delivery) ZIP code serving Discovery Bay, 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 94505 at a glance
| ZIP code | 94505 |
|---|---|
| Primary city | Discovery Bay |
| State | California (CA) |
| County | Contra Costa FIPS 06013 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 14,970 |
| Coordinates | 37.866380, -121.586800 |
How ZIP+4 works in 94505
The four digits after the hyphen encode a delivery segment inside 94505. 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 94505 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 94505.
| ZIP | City | Distance |
|---|---|---|
| 94514 | Byron, CA | 3.6 mi |
| 95391 | Tracy, CA | 6.7 mi |
| 94513 | Brentwood, CA | 6.7 mi |
| 94548 | Knightsen, CA | 8.3 mi |
| 95206 | Stockton, CA | 9.8 mi |
| 94561 | Oakley, CA | 10.4 mi |
| 95219 | Stockton, CA | 11.3 mi |
| 94511 | Bethel Island, CA | 11.6 mi |
| 94551 | Livermore, CA | 12 mi |
| 94531 | Antioch, CA | 12.1 mi |
| 95376 | Tracy, CA | 12.2 mi |
| 95203 | Stockton, CA | 15.1 mi |
Questions about 94505
What is the ZIP+4 code for 94505?
94505 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 94505, you need to look up a specific street address to get them.
What city is 94505?
94505 is assigned to Discovery Bay, 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.