ZIP Code 21817 — Crisfield, MD
21817 is a standard (street delivery) ZIP code serving Crisfield, Maryland, in Somerset 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 21817 at a glance
| ZIP code | 21817 |
|---|---|
| Primary city | Crisfield |
| State | Maryland (MD) |
| County | Somerset FIPS 24039 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 4,417 |
| Coordinates | 37.980810, -75.835370 |
How ZIP+4 works in 21817
The four digits after the hyphen encode a delivery segment inside 21817. 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 21817 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 21817.
| ZIP | City | Distance |
|---|---|---|
| 21838 | Marion Station, MD | 6.1 mi |
| 23427 | Saxis, VA | 8.1 mi |
| 21867 | Upper Fairmount, MD | 9.2 mi |
| 23426 | Sanford, VA | 9.5 mi |
| 21866 | Tylerton, MD | 10.2 mi |
| 21871 | Westover, MD | 10.3 mi |
| 21824 | Ewell, MD | 10.5 mi |
| 23409 | Mears, VA | 12.4 mi |
| 23488 | Withams, VA | 12.5 mi |
| 21821 | Deal Island, MD | 13.4 mi |
| 23440 | Tangier, VA | 13.4 mi |
| 21890 | Westover, MD | 14.2 mi |
Questions about 21817
What is the ZIP+4 code for 21817?
21817 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 21817, you need to look up a specific street address to get them.
What city is 21817?
21817 is assigned to Crisfield, Maryland, in Somerset 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.