Residential delivery area · Iowa
ZIP Code 51103: Sioux City, IA
ZIP code 51103 is in Sioux City, Iowa, entirely in Woodbury County (Census 2020 ZIP-county file). About 17,000 people live there (Census Bureau, ACS 2020-2024), the 3rd most populous of Sioux City's 8 residential ZIP codes. Median household income is $58,197 (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
- 12.1 sq mi · 1,400 people per sq mi
- PO Box ZIPs
- 51102 also use the name Sioux City
Where is ZIP code 51103?
51103 centers on 42.520°, -96.449° and covers 12.1 square miles of land plus 0.2 of water. It borders 7 ZIP codes: 51104, 51101, 51105, 68776, 51108, 51109, 51106.
The map draws ZIP code areas only. For the streets inside 51103, 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 51103 compare with the rest of Sioux City?
| Measure | 51103 | In Sioux City | In Woodbury County | In IA |
|---|---|---|---|---|
| People (ACS 2020-2024) | 16,895 | 3rd of 8 | 3rd of 26 | 51st of 970 |
| Median household income | $58k | 4th of 5 | 9th of 11 | 369th of 396 |
| Median home value | $143k | 4th of 6 | 10th of 14 | 344th of 423 |
Its median household income is higher than in 26% of U.S. residential ZIP codes, and it is denser than 81% 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 51103?
The 2020 Census counted 16,827 people in 51103; the ACS, which samples households over 2020-2024, estimates 16,895. Its boundary changed between the 2010 and 2020 censuses, so the two counts are not compared.
- People, ACS 2020-2024
- 16,895
- 2020 Census count
- 16,827
- Households
- 6,402
- Median age
- 35.5
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 51103?
Of the 16,895 people the ACS estimates in 51103, 25.9% are under 18 and 16.2% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (49.9%), then Hispanic or Latino (36.9%).
- Under 1825.9%
- 18 to 6457.9%
- 65 and older16.2%
- White, not Hispanic49.9%
- Hispanic or Latino36.9%
- Other or two or more5.6%
- Black, not Hispanic4.7%
- Asian, not Hispanic2.9%
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 51103 earn?
Median household income is $58,197 (ACS 2020-2024), the 9th highest of the 11 ranked ZIP codes in Woodbury County.
- Median household income
- $58,197±$5,883
- Income per person
- $27,717
- Below the poverty line
- 21.0%
- Unemployed (of the labor force)
- 3.4%
- Adults 25+ with a bachelor's degree
- 18.0%
- Adjusted gross income per tax return, 2022
- $49,3807,100 returns; wages 81% 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 51103?
FHFA's house price index for 51103, built from repeat sales and appraisals of the same homes, rose 106% from 2015 to 2025 and rose 58% from 2020 to 2025, and moved +6.4% in 2025.
- Median home value (owners' estimate)
- $142,900
- Median gross rent
- $906
- Homes owned by their occupants
- 65.6%
- Housing units
- 6,848
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 51103?
265 business establishments had a location in this ZIP code in 2023, 13 more than in 2018; the most are in other services (except public administration) (ZIP Code Business Patterns).
- Other services (except public administration)45
- Construction44
- Retail trade37
- Accommodation and food services29
- Health care and social assistance20
- Administrative and support and waste management and remediation services19
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 51103?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 51104 | Sioux City | 23,197 | $75k | 2.6 mi |
| 51101 | Sioux City | 1,031 | $15k | 3.3 mi |
| 51105 | Sioux City | 10,415 | $52k | 4.3 mi |
| 68776 | South Sioux City, NE | 15,373 | $69k | 4.3 mi |
| 51108 | Sioux City | 5,960 | $81k | 5.9 mi |
| 51109 | Sioux City | 3,606 | $79k | 6.3 mi |
| 51106 | Sioux City | 28,592 | $78k | 8.0 mi |
| 57049 | North Sioux City, SD | 7,962 | $93k | 3.1 mi (near) |
| 51111 | Sioux City | 39 | – | 7.6 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.