| District of Iowa | |
| Iowa City, 1846-1859 | |
| Burlington, 1849-1859 | |
| Dubuque, 1849-1882 | |
| Des Moines, 1859-1882 | |
| Keokuk, 1859-1882 | |
| Council Bluffs, 1870-1882 | |
| Northern District of Iowa | |
| Dubuque, 1882- | |
| Fort Dodge, 1882- | |
| Sioux City, 1882- | |
| Cedar Rapids, 1891- | |
| Waterloo, 1912- | |
| Mason City, 1923- | |
| Southern District of Iowa | |
| Council Bluffs, 1882- | |
| Des Moines, 1882- | |
| Keokuk, 1882- | |
| Creston, 1900- | |
| Davenport, 1904- | |
| Ottumwa, 1907- | |
| Rock Island, Illinois, 2003-2006 | |