Residential delivery area · Iowa
ZIP Code 51104: Sioux City, IA
ZIP code 51104 is in Sioux City, Iowa, entirely in Woodbury County (Census 2020 ZIP-county file). About 23,000 people live there (Census Bureau, ACS 2020-2024), the 2nd most populous of Sioux City's 8 residential ZIP codes. Median household income is $75,362 (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Sioux City · 8 residential ZIPs
- County
- Woodbury County
- Census places
- Sioux City
- Metro area
- Sioux City, IA-NE-SD
- House district
- IA-4 119th Congress
- State
- Iowa
- Time zone
- Central
- Land area
- 7.5 sq mi · 3,103 people per sq mi
- PO Box ZIPs
- 51102 also use the name Sioux City
Where is ZIP code 51104?
51104 centers on 42.535°, -96.403° and covers 7.5 square miles of land plus 0.0 of water. It borders 3 ZIP codes: 51103, 51105, 51108.
The map draws ZIP code areas only. For the streets inside 51104, 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 51104 compare with the rest of Sioux City?
| Measure | 51104 | In Sioux City | In Woodbury County | In IA |
|---|---|---|---|---|
| People (ACS 2020-2024) | 23,197 | 2nd of 8 | 2nd of 26 | 36th of 970 |
| Median household income | $75k | 3rd of 5 | 7th of 11 | 212th of 396 |
| Median home value | $211k | 1st of 6 | 7th of 14 | 159th of 423 |
Its median household income is higher than in 55% of U.S. residential ZIP codes, and it is denser than 89% 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 51104?
The 2020 Census counted 23,080 people in 51104; the ACS, which samples households over 2020-2024, estimates 23,197. Between the 2010 and 2020 censuses its population grew 4.4% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 23,197
- 2020 Census count
- 23,080+4.4% since 2010 (22,104)
- Households
- 8,729
- Median age
- 37.5
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 51104?
Of the 23,197 people the ACS estimates in 51104, 23.7% are under 18 and 15.6% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (63.1%), then Hispanic or Latino (20.3%).
- Under 1823.7%
- 18 to 6460.7%
- 65 and older15.6%
- White, not Hispanic63.1%
- Hispanic or Latino20.3%
- Other or two or more8.2%
- Black, not Hispanic5.3%
- Asian, not Hispanic3.1%
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 51104 earn?
Median household income is $75,362 (ACS 2020-2024), the 7th highest of the 11 ranked ZIP codes in Woodbury County. It is not measurably different from 2015-2019 ($78,487 in 2024 dollars): the change is within the surveys' margins of error.
- Median household income
- $75,362
- Income per person
- $36,752
- Below the poverty line
- 10.4%
- Unemployed (of the labor force)
- 4.6%
- Adults 25+ with a bachelor's degree
- 28.9%
- Adjusted gross income per tax return, 2022
- $69,21910,360 returns; wages 72% 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 51104?
FHFA's house price index for 51104, built from repeat sales and appraisals of the same homes, rose 82% from 2015 to 2025 and rose 47% from 2020 to 2025, and moved +4.6% in 2025.
- Median home value (owners' estimate)
- $211,100
- Median gross rent
- $998
- Homes owned by their occupants
- 64.5%
- Housing units
- 9,118
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 51104?
295 business establishments had a location in this ZIP code in 2023, 23 fewer than in 2018; the most are in health care and social assistance (ZIP Code Business Patterns).
- Health care and social assistance83
- Other services (except public administration)32
- Accommodation and food services27
- Construction24
- Retail trade24
- Finance and insurance19
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 51104?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 51103 | Sioux City | 16,895 | $58k | 2.6 mi |
| 51105 | Sioux City | 10,415 | $52k | 2.6 mi |
| 51108 | Sioux City | 5,960 | $81k | 3.4 mi |
| 51101 | Sioux City | 1,031 | $15k | 2.9 mi (near) |
| 57049 | North Sioux City, SD | 7,962 | $93k | 5.5 mi (near) |
| 68776 | South Sioux City, NE | 15,373 | $69k | 5.9 mi (near) |
| 51109 | Sioux City | 3,606 | $79k | 6.2 mi (near) |
| 51106 | Sioux City | 28,592 | $78k | 6.7 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.