Residential delivery area · Iowa
ZIP Code 51331: Arnolds Park, IA
ZIP code 51331 is in Arnolds Park, Iowa, entirely in Dickinson County (Census 2020 ZIP-county file). About 940 people live there (Census Bureau, ACS 2020-2024). Median household income is $89,167 (Census Bureau, ACS 2020-2024). By Census place, 73% of its land lies in Arnolds Park, and 4% in smaller places; 24% is outside any Census place.
- ACS2020-24
- Census2020
- FHFA2021
- ZBP2023
- IRS2022
- Town
- Arnolds Park · its only residential ZIP
- County
- Dickinson County
- Census places
- Arnolds Park
- Micro area
- Spirit Lake, IA
- House district
- IA-4 119th Congress
- State
- Iowa
- Time zone
- Central
- Land area
- 1.6 sq mi · 583 people per sq mi
Where is ZIP code 51331?
51331 centers on 43.360°, -95.131° and covers 1.6 square miles of land plus 0.9 of water. It borders 3 ZIP codes: 51355, 51351, 51360.
The map draws ZIP code areas only. For the streets inside 51331, 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 51331 compare with the rest of Dickinson County?
| Measure | 51331 | In Dickinson County | In IA |
|---|---|---|---|
| People (ACS 2020-2024) | 935 | 6th of 10 | 487th of 970 |
| Median household income | $89k | not ranked | not ranked |
| Median home value | $449k | not ranked | not ranked |
51331's income and home value are not ranked: it has fewer than 1,000 residents (935). Rankings use ZIP codes of 1,000 or more people living in households, with margins at most 25% of the figure.
It is denser than 73% of 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 51331?
The 2020 Census counted 1,102 people in 51331; the ACS, which samples households over 2020-2024, estimates 935. Between the 2010 and 2020 censuses its population fell 3.3% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 935±174 (90% margin)
- 2020 Census count
- 1,102−3.3% since 2010 (1,140)
- Households
- 522
- Median age
- 64.8
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 51331?
Of the 935 people the ACS estimates in 51331, 6.6% are under 18 and 49.1% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (97.9%).
- Under 186.6%
- 18 to 6444.3%
- 65 and older49.1%
- White, not Hispanic97.9%
- Other or two or more1.4%
- Hispanic or Latino0.7%
- 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 51331 earn?
Median household income is $89,167 (ACS 2020-2024). It rose from $60,200 in 2015-2019 (in 2024 dollars), a change larger than the surveys' margins of error.
- Median household income
- $89,167±$20,341
- Income per person
- $70,729
- Below the poverty line
- 5.8%
- Unemployed (of the labor force)
- 0.5%
- Adults 25+ with a bachelor's degree
- 40.7%
- Adjusted gross income per tax return, 2022
- $121,007680 returns; wages 33% 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 51331?
- Median home value (owners' estimate)
- $448,800
- Median gross rent
- $497
- Homes owned by their occupants
- 89.3%
- Housing units
- 1,618
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 51331?
92 business establishments had a location in this ZIP code in 2023, 5 fewer than in 2018; the most are in accommodation and food services (ZIP Code Business Patterns).
- Accommodation and food services33
- Retail trade15
- Other services (except public administration)8
- Real estate and rental and leasing6
- Arts, entertainment, and recreation6
- Transportation and warehousing5
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 51331?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 51355 | Okoboji | 1,048 | $72k | 2.1 mi |
| 51351 | Milford | 4,988 | $74k | 4.1 mi |
| 51360 | Spirit Lake | 8,653 | $76k | 5.6 mi |
| 51340 | Fostoria | 75 | $90k | 8.3 mi (near) |
| 51364 | Terril | 803 | $67k | 9.4 mi (near) |
| 51347 | Lake Park | 1,470 | $83k | 10.4 mi (near) |
| 51363 | Superior | 111 | $76k | 10.6 mi (near) |
| 51338 | Everly | 852 | $58k | 14.2 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.