ZIP Codes in Allentown, PA
Allentown uses 7 ZIP codes, all in Lehigh County. Pick one below for details, or look up the full nine-digit ZIP+4 for a specific street address.
All 7 Allentown ZIP codes
| ZIP | Type | County | Population |
|---|---|---|---|
| 18101 | standard | Lehigh | 6,120 |
| 18102 | standard | Lehigh | 51,001 |
| 18103 | standard | Lehigh | 48,746 |
| 18104 | standard | Lehigh | 48,683 |
| 18106 | standard | Lehigh | 6,226 |
| 18109 | standard | Lehigh | 18,446 |
| 18195 | standard | Lehigh | — |
Finding a ZIP+4 in Allentown
Knowing which of these 7 ZIP codes covers an address only gets you partway. The four-digit extension identifies the specific delivery point — typically one side of one block. Two houses facing each other on the same Allentown street almost always have different ZIP+4 codes even though they share all five leading digits.
Appending ZIP+4 to a mailing list?
Upload a CSV of Allentown addresses and download it complete.