ZIP Code 94021 — Loma Mar, CA
94021 is a standard (street delivery) ZIP code serving Loma Mar, California, in San Mateo 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 94021 at a glance
| ZIP code | 94021 |
|---|---|
| Primary city | Loma Mar |
| State | California (CA) |
| County | San Mateo FIPS 06081 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 321 |
| Coordinates | 37.250280, -122.249580 |
How ZIP+4 works in 94021
The four digits after the hyphen encode a delivery segment inside 94021. 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 94021 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 94021.
| ZIP | City | Distance |
|---|---|---|
| 94020 | La Honda, CA | 2.9 mi |
| 94060 | Pescadero, CA | 5.1 mi |
| 94074 | San Gregorio, CA | 7.4 mi |
| 95006 | Boulder Creek, CA | 7.7 mi |
| 94028 | Portola Valley, CA | 8.9 mi |
| 94022 | Los Altos, CA | 9.3 mi |
| 95014 | Cupertino, CA | 10.1 mi |
| 95017 | Davenport, CA | 10.1 mi |
| 94024 | Los Altos, CA | 10.8 mi |
| 95070 | Saratoga, CA | 10.9 mi |
| 94304 | Palo Alto, CA | 11.1 mi |
| 95007 | Brookdale, CA | 12.2 mi |
Questions about 94021
What is the ZIP+4 code for 94021?
94021 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 94021, you need to look up a specific street address to get them.
What city is 94021?
94021 is assigned to Loma Mar, California, in San Mateo 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.