| Census Year | Population | County Rank (if known) |
|---|---|---|
| 1838 | 241 | |
| 1840 | 475 | |
| 1844 | 1,112 | |
| 1846 | 1,758 | |
| 1847 | 1,779 | |
| 1848 | 2,140 | |
| 1850 | 3,007 | 24 |
| 1851 | 3,400 | |
| 1852 | 4,201 | |
| 1854 | 6,075 | |
| 1856 | 9,835 | |
| 1859 | 13,475 | |
| 1860 | 13,306 | 20 |
| 1863 | 13,495 | |
| 1865 | 14,376 | |
| 1867 | 16,228 | |
| 1869 | 18,113 | |
| 1870 | 19,731 | 21 |
| 1880 | 21,052 | 24 |
| 1890 | 20,233 | 30 |
| 1900 | 21,954 | 36 |
| 1910 | 19,050 | 44 |
| 1920 | 18,607 | 48 |
| 1930 | 19,206 | 43 |
| 1940 | 19,950 | 41 |
| 1950 | 19,401 | 43 |
| 1960 | 20,693 | 40 |
| 1970 | 19,868 | 38 |
| 1980 | 20,401 | 37 |
| 1990 | 19,444 | 35 |
| 2000 | 20,221 | 36 |
| 2010 | 20,638 | 33 |
Contributed by Cheryl Siebrass, June 2020. Source: U.S. Bureau of the Census, Decennial Census; 1900-1990 Censuses: Population of Counties by Decennial Census: 1900 to 1990 Compiled and edited by Richard L. Forstall, Population Division U.S. Bureau of the Census; 1850-1890 Censuses: Eleventh Census of the United States - 1890, Table 4. Prepared By: State Library of Iowa, State Data Center Program, 800-248-4483. Jones County 1852-1869 population totals extracted from the IAGenWeb State Census Project transcription by Polly Eckles.
