| City/County | Telephone Area Coce | Postcode |
| Zhengzhou | 0371 | 450000 |
| Zhumadian | 03011 | 463000 |
| Shangqiu | 0370 | 476000 |
| Anyang | 0372 | 455000 |
| Xinxiang | 0373 | 453000 |
| Xuchang | 0374 | 461000 |
| Pingdingshan | 0375 | 467000 |
| Xinyang | 0376 | 464000 |
| Nanyang | 0377 | 473000 |
| Kaifeng | 0378 | 475000 |
| Luoyang | 0379 | 471000 |
| Jiaozuo | 03811 | 454000 |
| Hebi | 03812 | 456600 |
| Luohe | 03813 | 462000 |
| Zhoukou | 03851 | 466000 |
| Sanmenxia | 03891 | 472000 |