ZIP Code 51231 - Archer Iowa
Overview
ZIP Code 51231 is located in Archer Iowa. Portions of 51231 are also in Carroll Township (Obrien County) and Summit Township (Obrien County) and Baker Township (Obrien County) and Dale Township (Obrien County). 51231 is entirely within Obrien County. Regionally, 51231 is located in the Sioux City Area.
ZIP Code 51231 Quick Stats
| ZIP Code Name | Archer |
| Primary County | Obrien County |
| ZIP Code Type | Standard |
| Population (2022) | 621 |
| Area Code(s) | 712 |
| Current Time | CDT |
ZIP Code 51231 Map
51231 Demographics
51231 can be classified socioeconomically as Middle Class class compared to other ZIP Codes in Iowa based on Median Household Income and Average Adjusted Gross Income. The majority race/ethnicity residing in 51231 is White. The current unemployment level in 51231 is 3.3%.
| Population | 621 |
| Population Growth Rate | 72.51% |
| Population Density | 27 People per Square Mile |
| Total Households | 89 |
| Median Household Income (2021) | $92,518 |
| Average Adjusted Gross Income (2021) | $131,470 |
| Current Unemployment Rate (May 2026) | 3.3% |
| Sales Tax Rate (2025) | 7% |
| Majority Race/Ethnicity | White - 100% |
51231 Race/Ethnicity Breakdown
| Race/Ethnicity | Total | Percentage |
|---|---|---|
| White | 659 | 100% |
| Black | 0 | 0% |
| Hispanic | 0 | 0% |
| Asian | 0 | 0% |
| Native American | 0 | 0% |
| Hawaiian/Pac. Islander | 0 | 0% |
51231 Educational Attainment Levels
| Highest Education Level | Total | Percentage |
|---|---|---|
| Less Than 1 Year of College | 17 | 10.18% |
| Bachelor Degree | 46 | 27.54% |
| High School Diploma | 63 | 37.72% |
| No High School Diploma | 0 | 0% |
| GED or Alternate | 3 | 1.8% |
| 1 or More Years of College | 18 | 10.78% |
| Associates Degree | 18 | 10.78% |
| Masters Degree | 2 | 1.2% |
| Professional Degree | 0 | 0% |
| Doctorate Degree | 0 | 0% |
51231 Geography
| Coordinates | 43.10399246, -95.74221039 |
| Adjacent ZIP Codes | |
| Cities/Towns in 51231 | |
| Region | Sioux City Area |
| Time Zone | Central Daylight Time |
| IANA Timezone | America/Chicago |
| Area | 23 Square Miles |
51231 Weather and Climate Data
| Plant Hardiness Zone | Zone 4b: -25F to -20F | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Average First Frost Date | October 1 - 10 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Average Last Frost Date | May 1 - 10 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Koppen-Geiger Climate Zone | Dfa - Humid Continental Hot Summers | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Ecoregion | 47a - Loess Prairies | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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