ZIP Code 92040 — Lakeside, CA
92040 is a standard (street delivery) ZIP code serving Lakeside, California, in San Diego 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 92040 at a glance
| ZIP code | 92040 |
|---|---|
| Primary city | Lakeside |
| State | California (CA) |
| County | San Diego FIPS 06073 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Los_Angeles |
| Population | 46,216 |
| Coordinates | 32.906650, -116.888750 |
How ZIP+4 works in 92040
The four digits after the hyphen encode a delivery segment inside 92040. 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 92040 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 92040.
| ZIP | City | Distance |
|---|---|---|
| 92021 | El Cajon, CA | 5 mi |
| 92071 | Santee, CA | 7.3 mi |
| 92019 | El Cajon, CA | 8.9 mi |
| 92020 | El Cajon, CA | 9 mi |
| 92064 | Poway, CA | 9 mi |
| 92131 | San Diego, CA | 9.8 mi |
| 92065 | Ramona, CA | 10.1 mi |
| 92119 | San Diego, CA | 10.7 mi |
| 91901 | Alpine, CA | 11.7 mi |
| 91942 | La Mesa, CA | 11.8 mi |
| 91941 | La Mesa, CA | 11.8 mi |
| 92128 | San Diego, CA | 12.4 mi |
Questions about 92040
What is the ZIP+4 code for 92040?
92040 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 92040, you need to look up a specific street address to get them.
What city is 92040?
92040 is assigned to Lakeside, California, in San Diego 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.