by Kristen Carney
Updated: December 17, 2024
The richest county in Iowa is Dallas County with an average household income of $134,691 as of 2023 and 111,092 people as of 2023 according to the most current Census data available (citation).
Rank | County | Population | Average Income | Median Income |
---|---|---|---|---|
1 | Dallas County | 111,092 | $134,691 | $102,349 |
2 | Warren County | 55,205 | $111,116 | $92,990 |
3 | Mills County | 14,633 | $109,588 | $87,810 |
4 | Johnson County | 157,528 | $108,967 | $74,721 |
5 | Polk County | 505,255 | $106,356 | $81,621 |
6 | Sioux County | 36,246 | $104,234 | $84,736 |
7 | Madison County | 16,971 | $103,385 | $89,542 |
8 | Plymouth County | 25,722 | $103,320 | $81,600 |
9 | Bremer County | 25,307 | $102,529 | $83,343 |
10 | Linn County | 228,972 | $101,721 | $76,421 |
11 | Scott County | 174,270 | $101,656 | $76,363 |
12 | Guthrie County | 10,722 | $100,399 | $79,981 |
13 | Marion County | 33,770 | $100,349 | $78,059 |
14 | Benton County | 25,796 | $99,622 | $84,742 |
15 | Dubuque County | 98,887 | $98,871 | $75,919 |
16 | Dickinson County | 18,056 | $98,855 | $74,570 |
17 | Adams County | 3,544 | $97,667 | $68,828 |
18 | Boone County | 26,590 | $97,592 | $79,741 |
19 | Winneshiek County | 19,815 | $97,497 | $75,652 |
20 | Delaware County | 17,600 | $95,969 | $76,205 |
We usually suggest using median income data – either instead of or in addition to – average income data as a true indicator of wealth. If you haven’t thought about median versus average since your last standardized test, you aren’t alone. Here’s what they are:
Now let’s say you had the following simplified set of income data.
Household 1: $30,000
Household 2: $50,000
Household 3: $1,000,000
The average income for this set is $360,000. The outlier data point ($1,000,000) skews the average WAY up. Conversely, the average income would be skewed WAY down if someone had an income of $500. The median income for the same data set is $50,000. Outlier data doesn’t skew the median.
So most business owners should use the median income as a true indicator of wealth, because it provides a more accurate representation of a typical income, especially in areas with significant income disparity.
If your target market is high-income households, the average income may be more relevant. This is because the average income can highlight the presence of a higher concentration of wealthy individuals, which is beneficial for luxury goods and services marketing. We’re using average income on this page because using the Census’s highest reported median value of $250,001 could result in multiple ties for the richest geography.
The Census' American Community Survey uses $250,000+ as a jam value for median income estimates to protect privacy, ensure data consistency, and simplify reporting. A "jam value" in survey data refers to a placeholder or default value used when actual data points are unavailable, incomplete, or exceed certain thresholds. We represent this jam value as $250,001 to make it easy for you to sort.
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United States Census Bureau. Annual Estimates of the Resident Population: April 1, 2020 to July 1, 2023. U.S. Census Bureau, Population Division. Web. May 2024. http://www.census.gov/.
United States Census Bureau. B01001 SEX BY AGE, 2023 American Community Survey 5-Year Estimates. U.S. Census Bureau, American Community Survey Office. Web. 12 December 2024. http://www.census.gov/.
United States Census Bureau. B19013 Median Household Income, 2023 American Community Survey 5-Year Estimates. U.S. Census Bureau, American Community Survey Office. Web. 12 December 2024. http://www.census.gov/.
United States Census Bureau. “DP03 SELECTED ECONOMIC CHARACTERISTICS.” 2023 American Community Survey 5-Year Estimates. U.S. Census Bureau, American Community Survey Office. Web. 12 December 2024. http://www.census.gov/.
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