Youngest ZIP codes in Sioux City, IA
These are the 7 ZIP codes in Sioux City, IA with the lowest median age, out of 7 with at least 1,000 residents. 51105 (Sioux City, 29.6), 51103 (Sioux City, 35.5) and 51106 (Sioux City, 36.4) lead the list. There is no single "best" ZIP code in Sioux City; the right one depends on who you want to reach, so the same ZIP codes are ranked several ways below.
Youngest ZIP codes in Sioux City
| Rank | ZIP | Mailing city | Median age | Residents | Households | Residential mailboxes |
|---|---|---|---|---|---|---|
| 1 | 51105 | Sioux City | 29.6 ±2.4 | 10,415 | 3,596 | — |
| 2 | 51103 | Sioux City | 35.5 ±2.3 | 16,895 | 6,402 | — |
| 3 | 51106 | Sioux City | 36.4 ±2.4 | 28,592 | 11,249 | 12,247 |
| 4 | 51104 | Sioux City | 37.5 ±2.4 | 23,197 | 8,729 | 9,023 |
| 5 | 51108 | Sioux City | 37.6 ±9.2 | 5,960 | 2,160 | 2,392 |
| 6 | 51109 | Sioux City | 39.4 ±11.8 | 3,606 | 1,447 | — |
| 7 | 51101 | Sioux City | 40.8 ±4.6 | 1,031 | 640 | — |
How we ranked them
Ranked by median age of all residents, lowest first (ACS 5-year estimates, 2020–2024). ZIP codes need at least 1,000 residents to be ranked; 7 of 8 qualify.
Which of these to mail, and why
Younger ZIP codes skew toward renters, students and young families: fitness, quick-service food, apartments, entertainment and first-time-buyer offers.
The top five ZIP codes on this list hold 32,136 households. Open any of them on the route map to see each carrier route's own figures before you choose.
Open 51105 on the EDDM route map
More rankings
- Richest ZIP codes in Sioux City
- ZIP codes with the highest home values in Sioux City
- ZIP codes with the highest homeownership in Sioux City
- ZIP codes with the most families with kids in Sioux City
- ZIP codes with the most new movers in Sioux City
- Oldest ZIP codes in Sioux City
- Fastest-growing ZIP codes in Sioux City
- Youngest ZIP codes in Woodbury County
- All Sioux City ZIP codes
Businesses that mail these ZIP codes
Map it and price it
EDDM guides
Frequently asked questions
- Which ZIP code in Sioux City has the lowest median age?
- 51105 (Sioux City), at 29.6 (±2.4), among 7 ZIP codes with at least 1,000 residents.
- How is this ranking calculated?
- Ranked by median age of all residents, lowest first (ACS 5-year estimates, 2020–2024).
- Why are some ZIP codes missing?
- ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.