ZIP Code 20155 — Gainesville, VA
20155 is a standard (street delivery) ZIP code serving Gainesville, Virginia, in Prince William 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 20155 at a glance
| ZIP code | 20155 |
|---|---|
| Primary city | Gainesville |
| State | Virginia (VA) |
| County | Prince William FIPS 51153 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 37,486 |
| Coordinates | 38.806460, -77.621450 |
How ZIP+4 works in 20155
The four digits after the hyphen encode a delivery segment inside 20155. 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 20155 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 20155.
| ZIP | City | Distance |
|---|---|---|
| 20169 | Haymarket, VA | 4.7 mi |
| 20143 | Catharpin, VA | 4.9 mi |
| 20109 | Manassas, VA | 4.9 mi |
| 20137 | Broad Run, VA | 5.8 mi |
| 20136 | Bristow, VA | 6 mi |
| 20110 | Manassas, VA | 8.3 mi |
| 20120 | Centreville, VA | 8.3 mi |
| 20152 | Chantilly, VA | 8.5 mi |
| 20121 | Centreville, VA | 8.7 mi |
| 20187 | Warrenton, VA | 8.9 mi |
| 20198 | The Plains, VA | 8.9 mi |
| 20181 | Nokesville, VA | 10.3 mi |
Questions about 20155
What is the ZIP+4 code for 20155?
20155 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 20155, you need to look up a specific street address to get them.
What city is 20155?
20155 is assigned to Gainesville, Virginia, in Prince William 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.