NumberResearchRecent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026
The Code holder is who opened each NPA-NXX prefix — not necessarily who holds the numbers. A prefix is 10,000 numbers, but under pooling its ten 1,000-number blocks are handed out individually, often to different carriers; the code holder may hold only one block, or none. The Thousands-blocks column shows how the ten blocks are really split — click which blocks → to see who holds each 1,000-number block and its last-4-digit range. Assignments are initial assignments; the current serving carrier may differ due to portability.
| Assigned | NPA-NXX | Thousands-blocks taken (last-4 opening) | Code holder | OCN | Rate center | State |
|---|---|---|---|---|---|---|
| 2013-06-18 | 810-216 | 0–9 XXXall 10 · 4 holders which blocks → | TELNET WORLDWIDE, INC. | 817J | PORT HURON | MI |
| 2004-12-06 | 810-988 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | MONTROSE | MI |
| 2002-03-27 | 810-400 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | MARINECITY | MI |
| 2002-03-27 | 810-616 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | FENTON | MI |
| 2002-03-27 | 810-800 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | HARTLAND | MI |
| 2002-03-27 | 810-828 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | DAVISON | MI |
| 2002-03-27 | 810-900 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | BRIGHTON | MI |
| 2002-01-16 | 810-857 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | ALGONAC | MI |
| 2001-09-21 | 810-539 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | DECKERVL | MI |
| 2001-07-17 | 810-729 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | CAPAC | MI |
| 2001-04-20 | 810-483 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | YALE | MI |
| 2001-03-16 | 810-448 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | DRYDEN | MI |
| 2001-02-15 | 810-452 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | LAPEER | MI |
| — | 810-396 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | FLINT | MI |
| — | 810-398 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | LEXINGTON | MI |
| — | 810-561 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | ST CLAIR | MI |
| — | 810-583 | not yet reported which blocks → | TELNET WORLDWIDE, INC. | 817J | SANDUSKY | MI |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.