County ZIP codes · Iowa · FIPS 19137
Montgomery County, IA ZIP Codes
Montgomery County, Iowa has 11 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 10 residential and 1 for PO boxes or a single organization. 6 of the residential ones lie mainly in Montgomery County and 4 mainly in a neighboring county; 8 cross the county line. Median household income ranges from $56,637 in 51566 (Red Oak) to $69,861 in 50864 (Villisca) (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
Where are the ZIP codes of Montgomery County?
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).
How different are its ZIP codes?
They carry 10 postal town names.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).
All 10 residential ZIP codes in Montgomery County
6 ZIP codes lie mainly in Montgomery County; 4 more reach into it from a neighboring county and follow the first table.
| In this county | ||||||
|---|---|---|---|---|---|---|
| 51566 | Red Oak | 7,010 | 40 | $57k | $134k | 91% |
| 50864 | Villisca | 1,662 | 11 | $70k | $110k | 65% |
| 51573 | Stanton | 979 | 17 | $86k | $134k | 100% |
| 51533 | Emerson | 844 | 11 | $69k | $137k | 55% |
| 51532 | Elliott | 644 | 11 | $65k | $99k | 86% |
| 50847 | Grant | 35 | 154 | $68k | $40k | 100% |
Partly in Montgomery County
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).
Which ZIP codes cross the county line?
8 ZIP codes of Montgomery County extend into another county. A ZIP code follows mail routes, not county borders.
| ZIP | In Montgomery | Elsewhere |
|---|---|---|
| 51566 | 91% | Page County 7%; Pottawattamie County 2% |
| 50864 | 65% | Page County 20%; Taylor County 9%; Adams County 4%; Cass County 2% |
| 51638 | 2% | Page County 98% |
| 51533 | 55% | Mills County 45% |
| 51532 | 86% | Pottawattamie County 11%; Cass County 3% |
| 51645 | 7% | Fremont County 57%; Mills County 30%; Page County 5% |
| 51541 | 16% | Mills County 71%; Pottawattamie County 13% |
| 50857 | 1% | Adams County 73%; Taylor County 26% |
Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).
PO Box and single-organization ZIP codes
| ZIP | Postal name |
|---|---|
| 51591 | Red Oak |
Source: GeoNames postal codes (CC BY 4.0).
Which first three digits do Montgomery County's ZIP codes use?
The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Montgomery County's ZIP codes use 3 prefixes: 508, 515 and 516.
| Prefix | Sectional center | Here | All codes |
|---|---|---|---|
| 508 | Des Moines, IA (SCF 500) | 3 | 28 |
| 515 | Omaha, NE (SCF 680) | 6 | 57 |
| 516 | Omaha, NE (SCF 680) | 2 | 21 |
Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.