Kansas Population as of 7/1/2008 Certified to the Secretary of State by Division of the Budget on 7/1/2009
| Jefferson County | 18421 |
| Cities |
| McLouth | 835 |
| Meriden | 755 |
| Nortonville | 585 |
| Oskaloosa | 1152 |
| Ozawkie | 560 |
| Perry | 845 |
| Valley Falls | 1156 |
| Winchester | 570 |
| Township |
| Delaware | 890 |
| Fairview | 1479 |
| Jefferson | 712 |
| Kaw | 1397 |
| Kentucky | 701 |
| Norton | 376 |
| Oskaloosa | 976 |
| Ozawkie | 873 |
| Rock Creek | 1971 |
| Rural | 824 |
| Sarcoxie | 958 |
| Union | 806 |