County ZIP codes · Iowa · FIPS 19033
Cerro Gordo County, IA ZIP Codes
Cerro Gordo County, Iowa has 18 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 17 residential and 1 for PO boxes or a single organization. 9 of the residential ones lie mainly in Cerro Gordo County and 8 mainly in a neighboring county; 12 cross the county line. Median household income ranges from $66,072 in 50401 (Mason City) to $99,643 in 50458 (Nora Springs) (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
Where are the ZIP codes of Cerro Gordo County?
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).
How different are its ZIP codes?
The middle half of its ranked ZIP codes (1,000+ people living in households) report median household incomes between $70,938 and $81,037.
They carry 17 postal town names.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).
All 17 residential ZIP codes in Cerro Gordo County
9 ZIP codes lie mainly in Cerro Gordo County; 8 more reach into it from a neighboring county and follow the first table.
| In this county | ||||||
|---|---|---|---|---|---|---|
| 50401 | Mason City | 28,703 | 194 | $66k | $147k | 100% |
| 50428 | Clear Lake | 9,071 | 77 | $81k | $283k | 100% |
| 50469 | Rockwell | 1,527 | 18 | $71k | $212k | 100% |
| 50482 | Ventura | 748 | 25 | $98k | $238k | 78% |
| 50464 | Plymouth | 694 | 28 | $92k | $197k | 55% |
| 50479 | Thornton | 655 | 11 | $69k | $121k | 72% |
| 50477 | Swaledale | 250 | 13 | $52k | $83k | 100% |
| 50433 | Dougherty | 157 | 3 | $69k | $86k | 53% |
| 50467 | Rock Falls | 63 | 56 | $64k | $150k | 100% |
Partly in Cerro Gordo County
| In this county | ||||||
|---|---|---|---|---|---|---|
| 50434 | Fertile | 396 | 39 | – | – | 40% |
| 50458 | Nora Springs | 2,094 | 30 | $100k | $158k | 36% |
| 50457 | Meservey | 463 | 14 | $47k | $91k | 30% |
| 50468 | Rockford | 1,617 | 16 | $73k | $174k | 25% |
| 50475 | Sheffield | 1,446 | 15 | $71k | $165k | 23% |
| 50449 | Klemme | 785 | 19 | $60k | $95k | 10% |
| 50444 | Hanlontown | 394 | 19 | $78k | $147k | 6% |
| 50456 | Manly | 1,699 | 34 | $81k | $125k | 2% |
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?
12 ZIP codes of Cerro Gordo County extend into another county. A ZIP code follows mail routes, not county borders.
| ZIP | In Cerro Gordo | Elsewhere |
|---|---|---|
| 50458 | 36% | Floyd County 53%; Mitchell County 11% |
| 50456 | 2% | Worth County 98% |
| 50468 | 25% | Floyd County 75% |
| 50475 | 23% | Franklin County 77% |
| 50449 | 10% | Hancock County 90% |
| 50482 | 78% | Hancock County 22% |
| 50464 | 55% | Worth County 42%; Mitchell County 3% |
| 50479 | 72% | Franklin County 28% |
| 50457 | 30% | Hancock County 30%; Franklin County 28%; Wright County 12% |
| 50434 | 40% | Worth County 60% |
| 50444 | 6% | Worth County 94% |
| 50433 | 53% | Floyd County 21%; Franklin County 19%; Butler County 7% |
Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).
PO Box and single-organization ZIP codes
| ZIP | Postal name |
|---|---|
| 50402 | Mason City |
Source: GeoNames postal codes (CC BY 4.0).
Which first three digits do Cerro Gordo County's ZIP codes use?
The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Every ZIP code of Cerro Gordo County starts with 504.
| Prefix | Sectional center | Here | All codes |
|---|---|---|---|
| 504 | Waterloo, IA (SCF 506) | 18 | 57 |
Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.