ILLINOIS BELL TEL CO
257 prefixes in 773 · initial assignments from the NANPA CO code file, 09/17/2026
| NPA-NXX | Rate center | OCN | Assigned | Pooled |
|---|---|---|---|---|
| 773-493 | CHICGOZN07 | 9329 | — | Yes |
| 773-506 | CHICGOZN02 | 9329 | — | — |
| 773-508 | CHICGOZN02 | 9329 | — | — |
| 773-509 | CHICGOZN02 | 9329 | — | — |
| 773-521 | CHICGOZN06 | 9329 | — | Yes |
| 773-522 | CHICGOZN06 | 9329 | — | — |
| 773-523 | CHICGOZN06 | 9329 | — | — |
| 773-525 | CHICGOZN04 | 9329 | — | — |
| 773-528 | CHICGOZN04 | 9329 | — | — |
| 773-529 | CHICGOZN04 | 9329 | — | — |
| 773-533 | CHICGOZN06 | 9329 | — | — |
| 773-534 | CHICGOZN06 | 9329 | — | — |
| 773-535 | CHICGOZN06 | 9329 | — | — |
| 773-536 | CHICGOZN07 | 9329 | — | Yes |
| 773-538 | CHICGOZN07 | 9329 | — | Yes |
| 773-539 | CHICGOZN02 | 9329 | — | — |
| 773-542 | CHICGOZN06 | 9329 | — | Yes |
| 773-545 | CHICGOZN03 | 9329 | — | — |
| 773-546 | CHICGOZN10 | 9329 | — | Yes |
| 773-548 | CHICGOZN07 | 9329 | — | Yes |
| 773-549 | CHICGOZN04 | 9329 | — | — |
| 773-553 | CHICGOZN06 | 9329 | — | Yes |
| 773-561 | CHICGOZN02 | 9329 | — | — |
| 773-568 | CHICGOZN10 | 9329 | — | — |
| 773-569 | CHICGOZN03 | 9329 | — | Yes |
| 773-579 | CHICGOZN06 | 9329 | — | — |
| 773-581 | CHICGOZN08 | 9329 | — | — |
| 773-582 | CHICGOZN08 | 9329 | — | — |
| 773-583 | CHICGOZN02 | 9329 | — | — |
| 773-585 | CHICGOZN08 | 9329 | — | — |
| 773-586 | CHICGOZN08 | 9329 | — | — |
| 773-588 | CHICGOZN02 | 9329 | — | — |
| 773-589 | CHICGOZN05 | 9329 | — | Yes |
| 773-591 | CHICGOZN01 | 9329 | — | — |
| 773-594 | CHICGOZN03 | 9329 | — | — |
| 773-601 | CHICGOZN11 | 9329 | — | — |
| 773-602 | CHICGOZN07 | 9329 | — | Yes |
| 773-604 | CHICGOZN02 | 9329 | — | — |
| 773-622 | CHICGOZN05 | 9329 | — | — |
| 773-624 | CHICGOZN07 | 9329 | — | — |
| 773-625 | CHICGOZN05 | 9329 | — | — |
| 773-626 | CHICGOZN05 | 9329 | — | — |
| 773-631 | CHICGOZN03 | 9329 | — | — |
| 773-637 | CHICGOZN05 | 9329 | — | — |
| 773-638 | CHICGOZN06 | 9329 | — | Yes |
| 773-643 | CHICGOZN07 | 9329 | — | Yes |
| 773-645 | CHICGOZN04 | 9329 | — | Yes |
| 773-646 | CHICGOZN09 | 9329 | — | — |
| 773-650 | CHICGOZN06 | 9329 | — | — |
| 773-651 | CHICGOZN07 | 9329 | — | — |
| 773-660 | CHICGOZN10 | 9329 | — | — |
| 773-665 | CHICGOZN04 | 9329 | — | — |
| 773-667 | CHICGOZN07 | 9329 | — | Yes |
| 773-674 | CHICGOZN06 | 9329 | 2008-05-15 | Yes |
| 773-684 | CHICGOZN07 | 9329 | — | Yes |
| 773-685 | CHICGOZN03 | 9329 | — | — |
| 773-686 | CHICGOZN11 | 9329 | — | — |
| 773-693 | CHICGOZN03 | 9329 | — | Yes |
| 773-694 | CHICGOZN11 | 9329 | — | Yes |
| 773-695 | CHICGOZN03 | 9329 | — | Yes |
| 773-702 | CHICGOZN07 | 9329 | — | — |
| 773-714 | CHICGOZN03 | 9329 | — | — |
| 773-721 | CHICGOZN09 | 9329 | — | — |
| 773-722 | CHICGOZN06 | 9329 | — | — |
| 773-723 | CHICGOZN07 | 9329 | — | — |
| 773-725 | CHICGOZN03 | 9329 | — | — |
| 773-728 | CHICGOZN02 | 9329 | — | — |
| 773-730 | CHICGOZN02 | 9329 | — | — |
| 773-731 | CHICGOZN09 | 9329 | — | — |
| 773-734 | CHICGOZN09 | 9329 | — | — |
| 773-735 | CHICGOZN08 | 9329 | — | — |
| 773-736 | CHICGOZN03 | 9329 | — | — |
| 773-737 | CHICGOZN08 | 9329 | — | — |
| 773-741 | CHICGOZN11 | 9329 | — | Yes |
| 773-743 | CHICGOZN02 | 9329 | — | — |
| 773-745 | CHICGOZN05 | 9329 | — | — |
| 773-752 | CHICGOZN07 | 9329 | — | — |
| 773-753 | CHICGOZN07 | 9329 | — | — |
| 773-755 | CHICGOZN04 | 9329 | — | — |
| 773-761 | CHICGOZN02 | 9329 | — | — |
| 773-762 | CHICGOZN06 | 9329 | — | Yes |
| 773-763 | CHICGOZN03 | 9329 | — | — |
| 773-764 | CHICGOZN02 | 9329 | — | — |
| 773-767 | CHICGOZN08 | 9329 | — | — |
| 773-768 | CHICGOZN09 | 9329 | — | — |
| 773-769 | CHICGOZN02 | 9329 | — | Yes |
| 773-772 | CHICGOZN04 | 9329 | — | — |
| 773-774 | CHICGOZN03 | 9329 | — | — |
| 773-775 | CHICGOZN03 | 9329 | — | — |
| 773-776 | CHICGOZN08 | 9329 | — | — |
| 773-777 | CHICGOZN03 | 9329 | — | — |
| 773-778 | CHICGOZN08 | 9329 | — | — |
| 773-779 | CHICGOZN10 | 9329 | — | — |
| 773-782 | CHICGOZN04 | 9329 | — | Yes |
| 773-783 | CHICGOZN07 | 9329 | — | — |
| 773-784 | CHICGOZN02 | 9329 | — | — |
| 773-785 | CHICGOZN10 | 9329 | — | — |
| 773-788 | CHICGOZN08 | 9329 | — | Yes |
| 773-792 | CHICGOZN03 | 9329 | — | — |
| 773-794 | CHICGOZN03 | 9329 | — | Yes |
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.