NumberResearch Membership · Data 09/29/2026

Recent prefix assignments

347 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/29/2026

Full prefixes (NXX) Thousands-blocks (1,000-number pools)

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, last 30 days
8X8, INC. 43
NEW CINGULAR WIRELESS PCS, LLC - DC 28
Rogers Communications Canada Inc. (Wireless) 23
NEW CINGULAR WIRELESS PCS, LLC - IL 23
ONVOY, LLC - CA 19
New assignments by month Sep 2026 Aug 2026 Jul 2026 Jun 2026 May 2026 Apr 2026 Mar 2026 Feb 2026 Jan 2026 Dec 2025 Nov 2025 Oct 2025
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Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 573-359 8XXX which blocks → SOUTHWESTERN BELL 9533 HAYTI MO
— 573-360 0–9 XXXall 10 · 7 holders which blocks → CHARTER IP ENABLED SERVICES, LLC 792K E PRAIRIE MO
— 573-361 0XXX1XXX2XXX4XXX5XXX6XXX7XXX9XXX · 6 holders which blocks → ONVOY, LLC - MO 093F ESSEX MO
— 573-362 0–9 XXXall 10 · 7 holders which blocks → ONVOY, LLC - MO 093F FISK MO
— 573-363 0XXX2XXX3XXX4XXX6XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 MACKSCREEK MO
— 573-364 not yet reported which blocks → EMBARQ MISSOURI, INC. DBA CENTURYLINK - MO 1811 ROLLA MO
— 573-365 not yet reported which blocks → SOUTHWESTERN BELL 9533 LKOZKOSBCH MO
— 573-366 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 FARMINGTON MO
— 573-368 none assigned yet which blocks → EMBARQ MISSOURI, INC. DBA CENTURYLINK - MO 1811 ROLLA MO
— 573-369 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 TUSCUMBIA MO
— 573-370 0–9 XXXall 10 · 8 holders which blocks → PEERLESS NETWORK OF MISSOURI, LLC - MO 225F GIDEON MO
— 573-371 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → PEERLESS NETWORK OF MISSOURI, LLC - MO 225F HOLCOMB MO
— 573-372 0XXX4XXX7XXX8XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 GRAVOIS ML MO
— 573-373 0XXX3XXX4XXX7XXX8XXX · 4 holders which blocks → BRIGHTSPEED OF EAST MISSOURI, LLC 1151 LADDONIA MO
— 573-374 not yet reported which blocks → SOUTHWESTERN BELL 9533 GRAVOIS ML MO
— 573-375 2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → UNITED STATES CELLULAR - MO 6275 ELDON MO
— 573-376 0XXX1XXX2XXX3XXX6XXX8XXX9XXX · 4 holders which blocks → ONVOY, LLC - MO 093F HORNERSVL MO
— 573-377 5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM MISSOURI, INC. 1885 STOVER MO
— 573-378 not yet reported which blocks → SOUTHWESTERN BELL 9533 VERSAILLES MO
— 573-379 6XXX which blocks → SOUTHWESTERN BELL 9533 PORTAGEVL MO
— 573-380 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 SIKESTON MO
— 573-381 0–9 XXXall 10 · 6 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MO 7218 CAPEGIRARD MO
— 573-382 8XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CAPEGIRARD MO
— 573-383 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → ONVOY, LLC - MO 093F CANTON MO
— 573-384 2XXX3XXX4XXX7XXX · 2 holders which blocks → WINDSTREAM MISSOURI, INC. 1885 SILEX MO
— 573-385 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → ONVOY, LLC - MO 093F LILBOURN MO
— 573-386 9XXX which blocks → KINGDOM TEL. CO. 1901 AUXVASSE MO
— 573-387 none assigned yet which blocks → KINGDOM TEL. CO. 1901 HATTON MO
— 573-388 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - MO 993E CAPEGIRARD MO
— 573-389 0XXX1XXX4XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → ONVOY, LLC - MO 093F OAK RIDGE MO
— 573-390 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 OLDAPPLETN MO
— 573-391 0–9 XXXall 10 · 7 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 PORTAGEVL MO
— 573-392 not yet reported which blocks → SOUTHWESTERN BELL 9533 ELDON MO
— 573-393 0XXX3XXX7XXX9XXX · 4 holders which blocks → BRIGHTSPEED OF EAST MISSOURI, LLC 1151 WESTQUINCY MO
— 573-394 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PEERLESS NETWORK OF MISSOURI, LLC - MO 225F RISCO MO
— 573-395 1XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → EMBARQ MISSOURI, INC. DBA CENTURYLINK - MO 1811 TAOS MO
— 573-396 0XXX3XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 RISCO MO
— 573-398 0–9 XXXall 10 · 8 holders which blocks → ONVOY, LLC - MO 093F SCOTT CITY MO
— 573-399 1XXX3XXX4XXX8XXX · 3 holders which blocks → WINDSTREAM MISSOURI, INC. 1885 NAYLOR MO
— 573-400 0XXX2XXX3XXX4XXX5XXX6XXX7XXX · 2 holders which blocks → ONVOY, LLC - MO 093F WESTQUINCY MO
— 573-401 0–9 XXXall 10 · 7 holders which blocks → PEERLESS NETWORK OF MISSOURI, LLC - MO 225F ST MARYS MO
— 573-402 0XXX1XXX2XXX3XXX6XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MO 4932 WARDELL MO
— 573-403 0XXX1XXX2XXX3XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PEERLESS NETWORK OF MISSOURI, LLC - MO 225F WYATT MO
— 573-404 0XXX1XXX2XXX3XXX4XXX5XXX8XXX · 5 holders which blocks → ONVOY, LLC - MO 093F QULIN MO
— 573-406 none assigned yet which blocks → SOUTHWESTERN BELL 9533 HANNIBAL MO
— 573-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MO
— 573-413 0–9 XXXall 10 · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 POPLAR BLF MO
— 573-414 0–9 XXXall 10 · 7 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 DEXTER MO
— 573-415 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MO 4932 JEFFERSNCY MO
— 573-419 0–9 XXXall 10 · 7 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CHAFFEE MO

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/29/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.