Onawa, IA ZIP code

The ZIP code for Onawa, Iowa is 51040. It is in Monona County.

51040

Population in these ZIPs: 3,500
Avg. median income: $71,200population-weighted
Typical home value: $157,000population-weighted

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Onawa, IA ZIP code list

Onawa, IA ZIP codes
ZIP code	Population	Median income	Typical home value
51040	3,500	$71,179	$157,000

Population and median household income: ACS 2020–2024 5-year estimates. Typical home value: Zillow Home Value Index (September 2026) where available, otherwise the ACS median owner-reported value. "PO Box" marks ZIP codes with no delivery area of their own. Methodology

Cities near Onawa

Castana 8 mi
Blencoe 8 mi
Whiting 9 mi
Moorhead 13 mi
Little Sioux 13 mi
Rodney 13 mi
Soldier 14 mi
Hornick 15 mi
Smithland 16 mi
Sloan 16 mi
Mapleton 17 mi
Pisgah 17 mi

Frequently asked questions

What is the ZIP code for Onawa, IA?

The ZIP code for Onawa, IA is 51040.

What county is Onawa, Iowa in?

Onawa ZIP codes are in Monona County.