ZIP Code 91803 — Alhambra, CA
91803 is a standard (street delivery) ZIP code serving Alhambra, California, in Los Angeles 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 91803 at a glance
| ZIP code | 91803 |
|---|---|
| Primary city | Alhambra |
| State | California (CA) |
| County | Los Angeles FIPS 06037 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 27,715 |
| Coordinates | 34.074900, -118.146240 |
How ZIP+4 works in 91803
The four digits after the hyphen encode a delivery segment inside 91803. 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 91803 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.
Other ZIP codes in Alhambra
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 91803.
| ZIP | City | Distance |
|---|---|---|
| 91801 | Alhambra, CA | 1.5 mi |
| 91754 | Monterey Park, CA | 1.7 mi |
| 90032 | Los Angeles, CA | 1.9 mi |
| 91030 | South Pasadena, CA | 2.5 mi |
| 91755 | Monterey Park, CA | 2.6 mi |
| 90063 | Los Angeles, CA | 3.1 mi |
| 91776 | San Gabriel, CA | 3.1 mi |
| 90022 | Los Angeles, CA | 3.5 mi |
| 90031 | Los Angeles, CA | 3.7 mi |
| 91770 | Rosemead, CA | 3.7 mi |
| 91108 | San Marino, CA | 3.8 mi |
| 90042 | Los Angeles, CA | 3.8 mi |
Questions about 91803
What is the ZIP+4 code for 91803?
91803 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 91803, you need to look up a specific street address to get them.
What city is 91803?
91803 is assigned to Alhambra, California, in Los Angeles 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.