NumberResearchRecent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026
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.
Most active assignees, all time — NPA 581
New assignments by month
Sep 2026
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Oct 2025
| Assigned | NPA-NXX | Thousands-blocks taken (last-4 opening) | Code holder | OCN | Rate center | State |
|---|---|---|---|---|---|---|
| 2018-07-12 | 581-879 | not yet reported which blocks → | Iristel Inc. | 154E | Chandler | — |
| 2018-07-11 | 581-508 | not yet reported which blocks → | Iristel Inc. | 154E | Baie-Comeau | — |
| 2018-07-11 | 581-509 | not yet reported which blocks → | Iristel Inc. | 154E | Carleton | — |
| 2018-07-11 | 581-512 | not yet reported which blocks → | Iristel Inc. | 154E | Bonaventure | — |
| 2018-07-11 | 581-513 | not yet reported which blocks → | Iristel Inc. | 154E | Matapedia | — |
| 2018-07-11 | 581-514 | not yet reported which blocks → | Iristel Inc. | 154E | New Richmond | — |
| 2018-06-18 | 581-710 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2018-06-11 | 581-507 | not yet reported which blocks → | Iristel Inc. | 154E | Baie-Comeau (Hauterive) | — |
| 2018-06-06 | 581-503 | not yet reported which blocks → | Iristel Inc. | 154E | Maria | — |
| 2018-06-06 | 581-504 | not yet reported which blocks → | Iristel Inc. | 154E | Matane | — |
| 2018-06-06 | 581-505 | not yet reported which blocks → | Iristel Inc. | 154E | Sept-Iles | — |
| 2018-03-07 | 581-709 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2017-10-06 | 581-502 | not yet reported which blocks → | Iristel Inc. | 154E | Levis | — |
| 2017-10-04 | 581-204 | not yet reported which blocks → | Iristel Inc. | 154E | Alma | — |
| 2017-10-04 | 581-707 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2017-10-04 | 581-708 | not yet reported which blocks → | Iristel Inc. | 154E | Chicoutimi | — |
| 2017-10-04 | 581-808 | not yet reported which blocks → | Iristel Inc. | 154E | St-Tite-des-Caps | — |
| 2017-07-26 | 581-800 | not yet reported which blocks → | Iristel Inc. | 154E | St-Felicien | — |
| 2017-05-25 | 581-706 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2016-12-09 | 581-805 | not yet reported which blocks → | Iristel Inc. | 154E | Rimouski | — |
| 2016-12-09 | 581-806 | not yet reported which blocks → | Iristel Inc. | 154E | Saint-Henri-de-Levis | — |
| 2016-12-09 | 581-807 | not yet reported which blocks → | Iristel Inc. | 154E | Montmagny | — |
| 2016-12-09 | 581-880 | not yet reported which blocks → | Iristel Inc. | 154E | Gaspe | — |
| 2016-10-27 | 581-501 | not yet reported which blocks → | Iristel Inc. | 154E | Levis | — |
| 2016-03-07 | 581-803 | not yet reported which blocks → | Iristel Inc. | 154E | St-Felicien | — |
| 2016-03-07 | 581-804 | not yet reported which blocks → | Iristel Inc. | 154E | St-Tite-des-Caps | — |
| 2016-02-19 | 581-812 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2016-02-18 | 581-802 | not yet reported which blocks → | Iristel Inc. | 154E | Thetford Mines | — |
| 2016-02-03 | 581-481 | not yet reported which blocks → | Iristel Inc. | 154E | Chibougamau | — |
| 2016-01-21 | 581-205 | not yet reported which blocks → | Iristel Inc. | 154E | Alma | — |
| 2016-01-21 | 581-801 | not yet reported which blocks → | Iristel Inc. | 154E | Riviere-du-Loup | — |
| 2012-06-01 | 581-200 | not yet reported which blocks → | Iristel Inc. | 154E | Alma | — |
| 2012-06-01 | 581-500 | not yet reported which blocks → | Iristel Inc. | 154E | Levis | — |
| 2012-04-05 | 581-705 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2012-03-22 | 581-704 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2012-03-19 | 581-221 | not yet reported which blocks → | Iristel Inc. | 154E | Chicoutimi | — |
| 2011-10-04 | 581-703 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2011-09-16 | 581-702 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2011-08-05 | 581-700 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2011-08-05 | 581-701 | not yet reported which blocks → | Iristel Inc. | 154E | Quebec | — |
| 2010-09-10 | 581-222 | not yet reported which blocks → | Iristel Inc. | 154E | Chicoutimi | — |
| 2010-09-10 | 581-333 | not yet reported which blocks → | Iristel Inc. | 154E | Thetford Mines | — |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.