| County | Population | County Seat | State | Links |
| Jefferson County, AL | 662047 | Birmingham | Alabama | View Public Records for Jefferson County, AL |
| Jefferson County, AR | 84278 | Pine Bluff | Arkansas | View Public Records for Jefferson County, AR |
| Jefferson County, CO | 527056 | Golden | Colorado | View Public Records for Jefferson County, CO |
| Jefferson County, FL | 12902 | Monticello | Florida | View Public Records for Jefferson County, FL |
| Jefferson County, GA | 17266 | Louisville | Georgia | View Public Records for Jefferson County, GA |
| Jefferson County, ID | 19155 | Rigby | Idaho | View Public Records for Jefferson County, ID |
| Jefferson County, IL | 40045 | Mount Vernon | Illinois | View Public Records for Jefferson County, IL |
| Jefferson County, IN | 31705 | Madison | Indiana | View Public Records for Jefferson County, IN |
| Jefferson County, IA | 16181 | Fairfield | Iowa | View Public Records for Jefferson County, IA |
| Jefferson County, KS | 18426 | Oskaloosa | Kansas | View Public Records for Jefferson County, KS |
| Jefferson County, KY | 693604 | Louisville | Kentucky | View Public Records for Jefferson County, KY |
| Jefferson County, LA | 455466 | Gretna | Louisiana | View Public Records for Jefferson County, LA |
| Jefferson County, MS | 9740 | Fayette | Mississippi | View Public Records for Jefferson County, MS |
| Jefferson County, MO | 198099 | Hillsboro | Missouri | View Public Records for Jefferson County, MO |
| Jefferson County, MT | 10049 | Boulder | Montana | View Public Records for Jefferson County, MT |
| Jefferson County, NE | 8333 | Fairbury | Nebraska | View Public Records for Jefferson County, NE |
| Jefferson County, NY | 111738 | Watertown | New York | View Public Records for Jefferson County, NY |
| Jefferson County, OH | 73894 | Steubenville | Ohio | View Public Records for Jefferson County, OH |
| Jefferson County, OK | 6818 | Waurika | Oklahoma | View Public Records for Jefferson County, OK |
| Jefferson County, OR | 19009 | Madras | Oregon | View Public Records for Jefferson County, OR |
| Jefferson County, PA | 45932 | Brookville | Pennsylvania | View Public Records for Jefferson County, PA |
| Jefferson County, TN | 44294 | Dandridge | Tennessee | View Public Records for Jefferson County, TN |
| Jefferson County, TX | 252051 | Beaumont | Texas | View Public Records for Jefferson County, TX |
| Jefferson County, WA | 25953 | Port Townsend | Washington | View Public Records for Jefferson County, WA |
| Jefferson County, WV | 42190 | Charles Town | West Virginia | View Public Records for Jefferson County, WV |
| Jefferson County, WI | 74021 | Jefferson | Wisconsin | View Public Records for Jefferson County, WI |