AMERICAN MESSAGING SERVICES, LLC
14 prefixes in 312 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 312-232 | CHICGOZN01 | 9748 | 2001-04-23 | — |
| 312-323 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-333 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-390 | CHICGOZN01 | 9748 | 2001-04-16 | — |
| 312-393 | CHICGOZN01 | 9748 | 2001-04-23 | — |
| 312-400 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-457 | CHICGOZN01 | 9748 | 2001-04-23 | — |
| 312-514 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-689 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-713 | CHICGOZN01 | 9748 | 2001-04-16 | — |
| 312-740 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-760 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-839 | CHICGOZN01 | 9748 | 2001-04-13 | — |
| 312-903 | CHICGOZN01 | 9748 | 2001-04-13 | — |
These are initial assignees from NANPA CO-code records — because of number portability, the current serving carrier of individual numbers may differ. Bulk export requires a membership.