Duncan ZIP codes, Iowa
No ZIP code is named for Duncan, IA; addresses there use a neighbouring town's name. 2 ZIP codes cover it: 50438 and 50423. Its area code is 641.
- USPS city name
- 0 ZIP codes
- Overlapping the city
- 2 more
- Population
- 21
- Area code
- 641
- County
- Hancock County
- State
- Iowa
NANPA lists no telephone rate centre for Duncan itself, so these are the area codes of the nearest one, Garner (0.0 miles). A town on an area-code boundary can differ from its neighbour.
ZIP codes covering Duncan
These ZIP codes cover part of Duncan but are addressed as somewhere else.
| ZIP | City | Type | Population | Median income | Median home |
|---|---|---|---|---|---|
50423 | Britt , IA | Standard | 2,291 | $73,151 | $118,900 |
50438 | Garner , IA | Standard | 3,995 | $70,350 | $197,600 |
Map of Duncan ZIP codes
The ZIP codes of Duncan, IA, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.
Towns near Duncan
The nearest larger towns are Garner (3,049 people, 5.0 mi), Britt (1,882 people, 5.1 mi) and Miller (25 people, 7.2 mi).
| Town | Population | Distance |
|---|---|---|
| Garner | 3,049 | 5.0 mi |
| Forest City | 4,290 | 10.8 mi |
| Clear Lake | 7,607 | 16.7 mi |
| Belmond | 2,694 | 18.7 mi |
| Mason City | 27,050 | 25.4 mi |
| Clarion | 2,770 | 26.0 mi |
| Algona | 5,377 | 26.8 mi |
More nearby: every ZIP code in Hancock County · Iowa ZIP codes
Cite this page
zipcodes.pro. “Duncan, IA ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ia/duncan
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