Kansas Population as of 7/1/2009 Certified to the Secretary of State by Division of the Budget on 7/1/2010
| Jefferson County | 18207 |
| Cities |
| McLouth | 823 |
| Meriden | 748 |
| Nortonville | 585 |
| Oskaloosa | 1136 |
| Ozawkie | 556 |
| Perry | 836 |
| Valley Falls | 1142 |
| Winchester | 562 |
| Township |
| Delaware | 883 |
| Fairview | 1461 |
| Jefferson | 706 |
| Kaw | 1381 |
| Kentucky | 695 |
| Norton | 373 |
| Oskaloosa | 967 |
| Ozawkie | 867 |
| Rock Creek | 1936 |
| Rural | 814 |
| Sarcoxie | 944 |
| Union | 798 |