Postal Code
51109
Postal Code 51109
Country United States
ISO Code US
ZIP Code 51109

Postal Information

Postal Code 51109
City Sioux City
County Woodbury
Region Iowa
Country United States

Nearby Postal Codes

Distances are calculated geographically from this postal code, not from administrative boundaries.

Postal Code City Region Coordinates
57049 North Sioux City South Dakota 3.8 km
51103 Sioux City Iowa 3.8 km
68776 South Sioux City Nebraska 7.2 km
51101 Sioux City Iowa 7.2 km
51104 Sioux City Iowa 7.7 km
57038 Jefferson South Dakota 8.2 km
51105 Sioux City Iowa 8.8 km
51108 Sioux City Iowa 9.2 km
68743 Jackson Nebraska 9.9 km
51106 Sioux City Iowa 11.2 km
57010 Burbank South Dakota 12.1 km
68731 Dakota City Nebraska 12.6 km
51111 Sioux City Iowa 13.1 km
51054 Sergeant Bluff Iowa 15.6 km
51102 Sioux City Iowa 15.8 km
68741 Hubbard Nebraska 16.9 km

Postal Hierarchy

ZIP Code51109

ZIP Code (5 digits) with optional ZIP+4 extension.

About ZIP Code 51109 in Sioux City, Iowa

ZIP Code 51109 for Sioux City, Iowa is part of the United States postal code system, which uses a numeric code of 5 (or 5+4) digits (e.g. 10001). Addresses here are organised as State → County → City. Within the code structure it maps to ZIP Code 51109.

Administratively it is recorded in Woodbury, Iowa within United States. Postal codes are assigned by delivery route rather than by administrative boundary, so a single code can cover more than one locality and a locality can fall under several codes.

No building-level records are held for this code in the imported dataset, so only the code and its location details are shown. The absence of records does not mean the zip code is unused.

Couriers, e-commerce checkout forms and address autocomplete tools all rely on the zip code to route mail and to check that a stated address matches the code. Because a zip code identifies a delivery area rather than a single building, two addresses that share the same code can still be some distance apart.

Always write United States ZIP Code in full when completing a form, including any leading zero. Enter a valid US ZIP Code, e.g. 10001 or 10001-1234. Data source: a third-party open dataset. This is a reference snapshot, not a live government feed, so confirm the code with the sender, carrier or postal authority before relying on it.

Buildings & Addresses for This Code

No building-level records were found for this postal code in the imported dataset.
Information provided on CodeReff is for reference purposes only. Always verify financial and banking details with the relevant institution before use.