United States Postal Code Database

United States uses a numeric code of 5 (or 5+4) digits (e.g. 10001). ZIP Code (5 digits) with optional ZIP+4 extension.

This database currently holds 42,605 ZIP Codes ranging from 00501 to 99929, linked to 0 building and address records. Because a single ZIP Code can cover more than one locality or delivery point, the lookup below groups addresses by code and lets you drill into the individual records.

Postal codes matter well beyond mail delivery. Couriers, e-commerce checkout forms and address autocomplete tools rely on the ZIP Code to route a parcel and to verify that the stated address matches the code. Addresses here are organised as State → County → City. The code itself is structured as ZIP Code → ZIP+4 → Delivery Point, which is postal geography and not the same as the administrative hierarchy. When you look up a code here, treat the associated name as a reference point rather than a full postal address — always confirm the street and house number with the sender or recipient before shipping.

Data source: a third-party open dataset. This is an imported reference dataset, not a live government feed; CodeReff does not independently verify each record, so codes may have changed since the snapshot was taken. Use the search box to look up a specific code, or browse the paginated table below.