| ZIP | County | State | Area Code | Time Zone |
| 52533 | Jefferson | IA | 641 | CST |
| 50601 | Hardin | IA | 641 | CST |
| 50001 | Warren | IA | 515 | CST |
| 50002 | Adair | IA | 641 | CST |
| 51062 | Plymouth | IA | 712 | CST |
| 50003 | Dallas | IA | 515 | CST |
| 50009 | Polk | IA | 515 | CST |
| 50830 | Union | IA | 641 | CST |
| 52530 | Wapello | IA | 641 | CST |
| 52201 | Washington | IA | 319 | CST |
| 51001 | Plymouth | IA | 712 | CST |
| 52142 | Fayette | IA | 563 | CST |
| 50510 | Buena Vista | IA | 712 | CST |
| 52531 | Monroe | IA | 641 | CST |
| 50005 | Marshall | IA | 641 | CST |
| 52202 | Linn | IA | 319 | CST |
| 50006 | Hardin | IA | 515 | CST |
| 50227 | Franklin | IA | 515 | CST |
| 50420 | Franklin | IA | 641 | CST |
| 50511 | Kossuth | IA | 515 | CST |
| 50007 | Polk | IA | 515 | CST |
| 51354 | Osceola | IA | 712 | CST |
| 50008 | Wayne | IA | 641 | CST |
| 50602 | Butler | IA | 319 | CST |
| 52171 | Fayette | IA | 563 | CST |
| 51002 | Buena Vista | IA | 712 | CST |
| 50603 | Chickasaw | IA | 641 | CST |
| 51003 | Sioux | IA | 712 | CST |
| 50009 | Polk | IA | 515 | CST |
| 51230 | Lyon | IA | 712 | CST |
| 52203 | Iowa | IA | 319 | CST |
| 52204 | Iowa | IA | 319 | CST |
| 52205 | Jones | IA | 319 | CST |
| 50208 | Jasper | IA | 641 | CST |
| 50010 | Story | IA | 515 | CST |
| 50011 | Story | IA | 515 | CST |
| 50012 | Story | IA | 515 | CST |
| 50013 | Story | IA | 515 | CST |
| 50014 | Story | IA | 515 | CST |
| 52205 | Jones | IA | 319 | CST |
| 52701 | Clinton | IA | 563 | CST |
| 52030 | Jackson | IA | 563 | CST |
| 50020 | Cass | IA | 712 | CST |
| 50021 | Polk | IA | 515 | CST |
| 50023 | Polk | IA | 515 | CST |
| 51004 | Woodbury | IA | 712 | CST |
| 50604 | Butler | IA | 319 | CST |
| 50250 | Guthrie | IA | 515 | CST |
| 51430 | Carroll | IA | 712 | CST |
| 51231 | Obrien | IA | 712 | CST |
| 50605 | Butler | IA | 641 | CST |
| 52619 | Lee | IA | 319 | CST |
| 52625 | Lee | IA | 319 | CST |
| 51520 | Crawford | IA | 712 | CST |
| 50831 | Union | IA | 641 | CST |
| 50606 | Fayette | IA | 563 | CST |
| 50514 | Emmet | IA | 712 | CST |
| 51331 | Dickinson | IA | 712 | CST |
| 50677 | Bremer | IA | 319 | CST |
| 51431 | Ida | IA | 712 | CST |
| 52002 | Dubuque | IA | 563 | CST |
| 51232 | Osceola | IA | 712 | CST |
| 51432 | Crawford | IA | 712 | CST |
| 52720 | Muscatine | IA | 563 | CST |
| 50836 | Taylor | IA | 641 | CST |
| 52206 | Benton | IA | 319 | CST |
| 50022 | Cass | IA | 712 | CST |
| 51433 | Sac | IA | 712 | CST |
| 50025 | Audubon | IA | 712 | CST |
| 51005 | Buena Vista | IA | 712 | CST |
| 50653 | Floyd | IA | 641 | CST |
| 50607 | Buchanan | IA | 319 | CST |
| 50608 | Butler | IA | 319 | CST |
| 52531 | Monroe | IA | 641 | CST |
| 51521 | Pottawattamie | IA | 712 | CST |
| 50047 | Warren | IA | 515 | CST |
| 50047 | Warren | IA | 515 | CST |
| 50515 | Palo Alto | IA | 712 | CST |
| 50516 | Webster | IA | 515 | CST |
| 50026 | Guthrie | IA | 641 | CST |
| 52207 | Jackson | IA | 563 | CST |
| 50517 | Kossuth | IA | 515 | CST |
| 52045 | Dubuque | IA | 563 | CST |
| 50027 | Mahaska | IA | 641 | CST |
| 50149 | Union | IA | 641 | CST |
| 50518 | Webster | IA | 515 | CST |
| 51654 | Fremont | IA | 712 | CST |
| 50645 | Chickasaw | IA | 641 | CST |
| 52533 | Jefferson | IA | 641 | CST |
| 51006 | Ida | IA | 712 | CST |
| 50028 | Jasper | IA | 641 | CST |
| 50029 | Guthrie | IA | 712 | CST |
| 52534 | Mahaska | IA | 641 | CST |
| 50074 | Ringgold | IA | 641 | CST |
| 50609 | Grundy | IA | 641 | CST |
| 50031 | Boone | IA | 515 | CST |
| 50310 | Polk | IA | 515 | CST |
| 52556 | Jefferson | IA | 641 | CST |
| 50833 | Taylor | IA | 712 | CST |
| 50225 | Marion | IA | 515 | CST |