County data desk
Which Missouri counties are the oldest? Stone County, at 33.1 percent.
One hundred and fifteen county equivalents, sorted by the share of residents aged 65 and over rather than the count. The top twenty, with the share, the count and the base population behind each one.
Methodology
- Metric
- Residents aged 65 and over as a share of total county population, sorted descending. Ties are broken by the larger count of residents aged 65 and over.
- Source
- U.S. Census Bureau, Population Estimates Program, Vintage 2024 county characteristics file cc-est2024-agesex-29.csv, columns AGE65PLUS_TOT and POPESTIMATE, rows coded YEAR 6.
- Reference date
- July 1, 2024.
- Item set
- All 115 Missouri county equivalents, the 114 counties plus the independent city of St. Louis. The top 20 by share are published here; the remaining 95 are held in the source file.
- Pulled
- September 10, 2026
- Licence
- Public domain, a work of the United States government.
| # | County | Share 65 and over | Aged 65 and over | Total population |
|---|---|---|---|---|
| 1 | Stone County | 33.1% | 10,800 | 32,630 |
| 2 | Benton County | 32.4% | 6,685 | 20,614 |
| 3 | Hickory County | 32.1% | 2,818 | 8,766 |
| 4 | Camden County | 31.1% | 13,726 | 44,135 |
| 5 | Ozark County | 29.5% | 2,686 | 9,090 |
| 6 | Worth County | 27.2% | 510 | 1,872 |
| 7 | St. Clair County | 25.8% | 2,539 | 9,848 |
| 8 | Holt County | 25.4% | 1,076 | 4,241 |
| 9 | Wayne County | 25.3% | 2,733 | 10,820 |
| 10 | Reynolds County | 25.3% | 1,497 | 5,927 |
| 11 | Chariton County | 25.2% | 1,865 | 7,397 |
| 12 | Atchison County | 25.2% | 1,296 | 5,139 |
| 13 | Gasconade County | 25.1% | 3,679 | 14,655 |
| 14 | Monroe County | 25.1% | 2,229 | 8,890 |
| 15 | Douglas County | 24.9% | 3,055 | 12,290 |
| 16 | Dade County | 24.6% | 1,875 | 7,622 |
| 17 | Morgan County | 24.4% | 5,457 | 22,399 |
| 18 | Mercer County | 24.2% | 836 | 3,452 |
| 19 | Ralls County | 23.9% | 2,508 | 10,499 |
| 20 | Putnam County | 23.9% | 1,085 | 4,539 |
Statewide, 18.7 percent of Missouri residents are aged 65 and over. Every county in this table sits above that line.
Where the oldest counties are
Sorted by share, the ranking has almost nothing in common with a ranking by count. Stone County leads at 33.1 percent on a population of 32,630. Benton follows at 32.4 percent, Hickory at 32.1 percent and Camden at 31.1 percent. All four sit in the lake and Ozark tier of southern Missouri, and none of them would appear near the top of a table sorted by the number of older adults.
The pattern in the lower half of the table is different again. Worth, Holt, Atchison, Mercer and Putnam are small northern counties, several of them under 5,000 residents in total, where a high share reflects decades of out migration by younger residents rather than any inflow of older ones. A share is a ratio, and it can rise because the numerator grew or because the denominator shrank.
At the bottom of the statewide list, Pulaski County reports 10.1 percent, the lowest share in Missouri, then Johnson County at 13.9 percent and Boone County at 14.5 percent. Each hosts a large institutional or student population that enlarges the denominator without adding to the numerator.
How the St. Louis region places
None of the seven Missouri county equivalents inside the St. Louis region reaches this top 20. Franklin County places highest among them at 20.3 percent, then St. Louis County at 20.1 percent and Warren County at 19.5 percent. St. Charles County reports 18.1 percent, Jefferson County 17.9 percent, the city of St. Louis 16.8 percent and Lincoln County 15.5 percent, the lowest share of the seven.
That is a distribution question rather than a ranking failure. Metropolitan counties hold large populations across every age band, so a metropolitan county can carry tens of thousands of older adults while sitting near the statewide median on share. Both readings are true at once, which is why this desk publishes them as two separate pages. The regional counts are on the county ranking page.
Cautions
Shares in very small counties move on small absolute changes. Worth County's 27.2 percent rests on 510 residents aged 65 and over, so a shift of a few dozen people moves the figure by a full percentage point. Read the smallest rows with that in mind.
This table describes residency by age. It is not a measure of health, disability, income or need for assistance, and this desk makes no such claim from it. Sources, column codes and limits are set out on the methodology page.
Back to the region at a glance · Sources, vintage and limits