Median Age in Marion County, IA
ACS 2024 5-Year Estimates
39.9 years
Rank #2,145/3,222 · #73 in IA
33th
Marion 39.9 years
IA 38.6 years +3.4%
US 38.9 years +2.6%
Median Age Trend
Rankings →Percentile Rank Over Time
Year-over-Year Age Change
National Distribution
How Marion County's median age of 39.9 years compares to all 3,222 U.S. counties. Values range from 21.4 years to 86.2 years.
Distribution of Median Age Across All Counties
Ranking Context
Counties ranked closest to Marion County for median age.
Nearby Rankings
Full ranking →| #2,142 | St. Clair County, IL | 39.9 years |
| #2,143 | Benton County, IN | 39.9 years |
| #2,144 | Clark County, IN | 39.9 years |
| #2,145 | Marion County, IA | 39.9 years |
| #2,146 | Saline County, KS | 39.9 years |
| #2,147 | Oldham County, KY | 39.9 years |
| #2,148 | Caroline County, MD | 39.9 years |
About Median Age
Marion County, Iowa has a median age of 39.9 years, ranking #2,145 of 3,222 counties nationwide — 2.6% above the national value of 38.9 years. Within Iowa, it ranks #73 of 99. This places it in the 33th percentile nationally.
The median age of the total population. Source: U.S. Census Bureau, American Community Survey 2024 5-Year Estimates. All values are estimates derived from survey samples and are subject to margin of error. For more information, see our methodology.