NumberResearchRecent prefix assignments
369 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/18/2026
Which carriers received which NPA-NXX prefixes, and where. Assignments are initial assignments from NANPA records — because of number portability, the current serving carrier of individual numbers may differ. For finer-grained activity, see the thousands-block view above.
Most active assignees, last 30 days
New assignments by month
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| Assigned | NPA-NXX | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|
| 313-834 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-835 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-836 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-837 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-838 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-839 | MICHIGAN BELL TEL CO | 9323 | DETROITZN2 | MI | |
| 313-840 | AMERICAN MESSAGING SERVICES, LLC | 9748 | DETROITZN5 | MI | |
| 313-841 | MICHIGAN BELL TEL CO | 9323 | DETROITZN6 | MI | |
| 313-842 | MICHIGAN BELL TEL CO | 9323 | DETROITZN6 | MI | |
| 313-843 | MICHIGAN BELL TEL CO | 9323 | DETROITZN6 | MI | |
| 313-845 | MICHIGAN BELL TEL CO | 9323 | DETROITZN6 | MI | |
| 313-846 | MICHIGAN BELL TEL CO | 9323 | DETROITZN6 | MI | |
| 313-849 | MICHIGAN BELL TEL CO | 9323 | DETROITZN6 | MI | |
| 313-850 | OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC | 2964 | DETROITZN5 | MI | |
| 313-851 | AMERICAN MESSAGING SERVICES, LLC | 9748 | DETROITZN6 | MI | |
| 313-852 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-854 | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | DETROITZN6 | MI | |
| 313-859 | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | DETROITZN5 | MI | |
| 313-861 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-862 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-863 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-864 | MICHIGAN BELL TEL CO | 9323 | DETROITZN4 | MI | |
| 313-865 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-866 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-867 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-868 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-869 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-870 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-871 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-872 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-873 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-874 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-875 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-876 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-877 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-878 | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | DETROITZN5 | MI | |
| 313-879 | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | DETROITZN1 | MI | |
| 313-881 | MICHIGAN BELL TEL CO | 9323 | DETROITZN2 | MI | |
| 313-882 | MICHIGAN BELL TEL CO | 9323 | DETROITZN2 | MI | |
| 313-883 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-884 | MICHIGAN BELL TEL CO | 9323 | DETROITZN2 | MI | |
| 313-885 | MICHIGAN BELL TEL CO | 9323 | DETROITZN2 | MI | |
| 313-886 | MICHIGAN BELL TEL CO | 9323 | DETROITZN2 | MI | |
| 313-887 | LEVEL 3 COMMUNICATIONS, LLC - MI | 6120 | DETROITZN1 | MI | |
| 313-891 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-892 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-893 | MICHIGAN BELL TEL CO | 9323 | DETROITZN3 | MI | |
| 313-894 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-895 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI | |
| 313-896 | MICHIGAN BELL TEL CO | 9323 | DETROITZN1 | MI |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/18/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.