NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026

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, all time — NPA 641
WINDSTREAM IOWA COMMUNICATIONS, INC. 60
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 46
UNITED STATES CELLULAR - IA 39
WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 32
QWEST CORPORATION 30
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
— 641-474 none assigned yet which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 GREEN MT IA
— 641-475 8XXX which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 HAVERHILL IA
— 641-476 8XXX which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 LAUREL IA
— 641-477 not yet reported which blocks → MINERVA VALLEY TEL. CO., INC. 1246 CLEMONS IA
— 641-478 8XXX which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 FERGUSON IA
— 641-479 0XXX3XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 LE GRAND IA
— 641-482 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 MELBOURNE IA
— 641-483 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 STATE CTR IA
— 641-484 0XXX which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 TOLEDO IA
— 641-485 none assigned yet which blocks → UNITED STATES CELLULAR - IA 6266 MARSHALLTN IA
— 641-486 not yet reported which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 UNION IA
— 641-487 not yet reported which blocks → MINERVA VALLEY TEL. CO., INC. 1246 ZEARING IA
— 641-488 8XXX which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 ALBION IA
— 641-489 3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 CHELSEA IA
— 641-492 2XXX3XXX4XXX5XXX7XXX8XXX · 5 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 MONTOUR IA
— 641-493 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 RHODES IA
— 641-494 4XXX6XXX7XXX8XXX9XXX which blocks → QWEST CORPORATION 9631 MASON CITY IA
— 641-495 not yet reported which blocks → FRONTIER COMMUNICATIONS OF IOWA, INC. 1127 GOODELL IA
— 641-496 not yet reported which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 LISCOMB IA
— 641-497 not yet reported which blocks → HEART OF IOWA COMMUNICATIONS COOPERATIVE - IA 1297 NEWPROVDNC IA
— 641-498 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 GILMAN IA
— 641-499 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 GARWIN IA
— 641-502 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 MELBOURNE IA
— 641-503 0XXX2XXX3XXX4XXX5XXX8XXX · 4 holders which blocks → ONVOY, LLC - IA 221F MOUNT AYR IA
— 641-504 not yet reported which blocks → T-MOBILE USA, INC. 6529 OSKALOOSA IA
— 641-507 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 BAXTER IA
— 641-510 not yet reported which blocks → T-MOBILE USA, INC. 6529 GRINNELL IA
— 641-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IA
— 641-512 8XXX9XXX which blocks → UNITED STATES CELLULAR - IA 6266 MASON CITY IA
— 641-515 not yet reported which blocks → IA
— 641-521 none assigned yet which blocks → UNITED STATES CELLULAR - IA 6266 NEWTON IA
— 641-522 not yet reported which blocks → BROOKLYN MUTUAL TEL. CO. 1113 BROOKLYN IA
— 641-524 not yet reported which blocks → COON VALLEY COOP. TEL. ASSN., INC. 1137 MENLO IA
— 641-525 2XXX5XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 CLEAR LAKE IA
— 641-526 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 KELLOGG IA
— 641-527 not yet reported which blocks → LYNNVILLE TELEPHONE COMPANY 1232 LYNNVILLE IA
— 641-528 0XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 MALCOM IA
— 641-529 8XXX9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 CLEAR LAKE IA
— 641-530 4XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 MASON CITY IA
— 641-533 not yet reported which blocks → GRAND RIVER MUTUAL TEL CO 1888 DERBY IA
— 641-534 2XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 LACONA IA
— 641-535 0XXX3XXX5XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 RUSSELL IA
— 641-541 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 SIGOURNEY IA
— 641-555 not yet reported which blocks → MULTIPLE OCN LISTING MULT DIR ASST IA
— 641-561 not yet reported which blocks → WINNEBAGO COOP. TEL. ASSN. - IA 1337 BUFFALOCTR IA
— 641-562 not yet reported which blocks → WINNEBAGO COOP. TEL. ASSN. - IA 1337 BUFFALOCTR IA
— 641-563 not yet reported which blocks → IA
— 641-565 not yet reported which blocks → WINNEBAGO COOP. TEL. ASSN. - IA 1337 CRYSTAL LK IA
— 641-566 not yet reported which blocks → WINNEBAGO COOP. TEL. ASSN. - IA 1337 RAKE IA
— 641-567 not yet reported which blocks → WINNEBAGO COOP. TEL. ASSN. - IA 1337 LELAND IA

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.