Residential delivery area · Iowa
ZIP Code 51535: Griswold, IA
ZIP code 51535 uses the postal name Griswold, Iowa and lies mostly in Cass County (56% of its land) with the rest in Pottawattamie County (Census 2020 ZIP-county file). About 1,700 people live there (Census Bureau, ACS 2020-2024). Median household income is $76,371 (Census Bureau, ACS 2020-2024). By Census place, under 1% of its land lies in Griswold; more than 99% is outside any Census place.
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Griswold · its only residential ZIP
- County
- Cass County (56%); Pottawattamie County (44%)
- Census places
- Griswold
- House districts
- IA-3 (56%), IA-4 (44%) 119th Congress, by share of land
- State
- Iowa
- Time zone
- Central
- Land area
- 135.3 sq mi · 13 people per sq mi
Where is ZIP code 51535?
51535 centers on 41.226°, -95.127° and covers 135.3 square miles of land plus 0.0 of water. It borders 10 ZIP codes: 51532, 51544, 50843, 50022, 51525, 51560, 51566, 51541, 51577, 50864.
The map draws ZIP code areas only. For the streets inside 51535, open its center on OpenStreetMap.
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries and the 2023 Gazetteer (2020 ZCTAs); ZIP-to-county shares, Census places and House districts (119th Congress) from the Census 2020 relationship files (shares of land); metro area from the OMB delineation (July 2023); town name and time zone from simplemaps US ZIP Codes (CC BY 4.0).
How does 51535 compare with the rest of Cass County?
| Measure | 51535 | In Cass County | In IA |
|---|---|---|---|
| People (ACS 2020-2024) | 1,697 | 2nd of 13 | 315th of 970 |
| Median household income | $76k | 1st of 5 | 198th of 396 |
| Median home value | $152k | 3rd of 5 | 321st of 423 |
Its median household income is higher than in 57% of U.S. residential ZIP codes, and it is denser than 19% of all U.S. residential ZIP codes. ZIP codes at the ACS caps ($250,000 or more for household income, $2,000,000 or more for home value) share the top rank.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B19013, B25077); ranks by PlainZIP over residential ZIP codes (ZCTAs).
How many people live in 51535?
The 2020 Census counted 1,764 people in 51535; the ACS, which samples households over 2020-2024, estimates 1,697. Between the 2010 and 2020 censuses its population fell 8.3% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 1,697±226 (90% margin)
- 2020 Census count
- 1,764−8.3% since 2010 (1,923)
- Households
- 740
- Median age
- 50.4
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B01002, B11001); 2020 Census (DHC P1); 2010 Census (SF1 P1).
Who lives in 51535?
Of the 1,697 people the ACS estimates in 51535, 20.7% are under 18 and 26.3% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (95.0%).
- Under 1820.7%
- 18 to 6452.9%
- 65 and older26.3%
- White, not Hispanic95.0%
- Other or two or more4.1%
- Hispanic or Latino0.9%
- Black, not Hispanic0.0%
- Asian, not Hispanic0.0%
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01001 age by sex, B03002 Hispanic or Latino origin by race); shares of the estimated population, small ZIP codes carry wide margins.
What do households in 51535 earn?
Median household income is $76,371 (ACS 2020-2024), the highest of the 5 ranked ZIP codes in Cass County. It is not measurably different from 2015-2019 ($75,450 in 2024 dollars): the change is within the surveys' margins of error.
- Median household income
- $76,371±$8,928
- Income per person
- $43,285
- Below the poverty line
- 7.9%
- Unemployed (of the labor force)
- 0.9%
- Adults 25+ with a bachelor's degree
- 22.6%
- Adjusted gross income per tax return, 2022
- $72,757820 returns; wages 59% of AGI (IRS)
Source: U.S. Census Bureau, ACS 2020-2024 and 2015-2019 5-year estimates (B19013, B19301, B17001, B23025, B15003; 2015-2019 dollars converted with the BLS CPI-U, 1.22699); IRS Statistics of Income, ZIP code data, tax year 2022 (adjusted gross income per return, filed under the address on the return).
What are homes worth in 51535?
FHFA's house price index for 51535, built from repeat sales and appraisals of the same homes, rose 119% from 2015 to 2025 and rose 67% from 2020 to 2025.
- Median home value (owners' estimate)
- $152,300
- Median gross rent
- $950
- Homes owned by their occupants
- 78.6%
- Housing units
- 791
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B25077, B25064, B25003, B25001); FHFA House Price Index, annual five-digit ZIP, updated 2026-03-31.
What businesses are in 51535?
49 business establishments had a location in this ZIP code in 2023, 3 more than in 2018; the most are in other services (except public administration) (ZIP Code Business Patterns).
- Other services (except public administration)9
- Construction5
- Transportation and warehousing5
- Retail trade4
- Finance and insurance4
- Health care and social assistance4
Source: U.S. Census Bureau, ZIP Code Business Patterns 2023 and 2018 (establishments with paid employees, by the business's ZIP code).
Which ZIP codes are next to 51535?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 51532 | Elliott | 644 | $65k | 6.2 mi |
| 51544 | Lewis | 793 | $48k | 6.2 mi |
| 50843 | Cumberland | 540 | $56k | 12.6 mi |
| 50022 | Atlantic | 8,526 | $63k | 14.5 mi |
| 51525 | Carson | 1,067 | $82k | 15.2 mi |
| 51560 | Oakland | 1,772 | $76k | 15.5 mi |
| 51566 | Red Oak | 7,010 | $57k | 15.6 mi |
| 51541 | Henderson | 273 | $92k | 16.2 mi |
| 51577 | Walnut | 1,561 | $72k | 16.9 mi |
| 50864 | Villisca | 1,662 | $70k | 19.3 mi |
| 50847 | Grant | 35 | $68k | 9.5 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.