NumberResearch Membership · Data 09/19/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026

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 563
QWEST CORPORATION 54
UNITED STATES CELLULAR - IA 33
WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 26
T-MOBILE USA, INC. 25
WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 22
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
— 563-569 0XXX2XXX3XXX4XXX5XXX6XXX7XXX · 6 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 PROTIVIN IA
— 563-570 not yet reported which blocks → T-MOBILE USA, INC. 6529 DAVENPORT IA
— 563-571 not yet reported which blocks → T-MOBILE USA, INC. 6529 MUSCATINE IA
— 563-574 not yet reported which blocks → F&B COMMUNICATIONS, INC. - IA 4245 DELMAR IA
— 563-577 not yet reported which blocks → PRESTON TEL. CO. 1276 GOOSE LAKE IA
— 563-578 6XXX7XXX9XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 SUMNER IA
— 563-579 not yet reported which blocks → T-MOBILE USA, INC. 6529 DAVENPORT IA
— 563-580 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 DUBUQUE IA
— 563-581 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 DUBUQUE IA
— 563-582 not yet reported which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-583 not yet reported which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-584 not yet reported which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-585 not yet reported which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-586 8XXX which blocks → ACE TEL. ASSN. - IA 1346 HARPESFRRY IA
— 563-587 8XXX9XXX · 2 holders which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-588 not yet reported which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-589 not yet reported which blocks → QWEST CORPORATION 9631 DUBUQUE IA
— 563-590 none assigned yet which blocks → UNITED STATES CELLULAR - IA 6266 DUBUQUE IA
— 563-593 not yet reported which blocks → T-MOBILE USA, INC. 6529 CLINTON IA
— 563-599 none assigned yet which blocks → UNITED STATES CELLULAR - IA 6266 DUBUQUE IA
— 563-605 3XXX4XXX5XXX6XXX8XXX · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 POSTVILLE IA
— 563-611 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IA
— 563-633 0XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 ARLINGTON IA
— 563-637 4XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 MAYNARD IA
— 563-641 not yet reported which blocks → IA
— 563-649 0XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 ATALISSA IA
— 563-650 none assigned yet which blocks → T-MOBILE USA, INC. 6529 DAVENPORT IA
— 563-652 8XXX which blocks → QWEST CORPORATION 9631 MAQUOKETA IA
— 563-659 6XXX7XXX · 2 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 DE WITT IA
— 563-661 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → ONVOY, LLC - IA 221F MAQUOKETA IA
— 563-672 not yet reported which blocks → ANDREW TEL. CO., INC. 1097 ANDREW IA
— 563-673 not yet reported which blocks → BALDWIN NASHVILLE TEL. CO., INC. 1107 BALDWIN IA
— 563-674 2XXX3XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 DELMAR IA
— 563-677 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 CHARLOTTE IA
— 563-678 not yet reported which blocks → LOST NATION-ELWOOD TEL. CO. 1229 LOSTNATION IA
— 563-682 not yet reported which blocks → MILES COOP. TEL. ASSN. 1242 MILES IA
— 563-686 not yet reported which blocks → CASCADE COMMUNICATIONS COMPANY 1118 OTTERCREEK IA
— 563-687 4XXX7XXX8XXX · 2 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 SABULA IA
— 563-689 not yet reported which blocks → PRESTON TEL. CO. 1276 PRESTON IA
— 563-690 8XXX which blocks → PAETEC ITEL, LLC 829J DUBUQUE IA
— 563-700 not yet reported which blocks → IA
— 563-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IA
— 563-712 not yet reported which blocks → IA
— 563-724 2XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 MOSCOW IA
— 563-732 not yet reported which blocks → WILTON TEL. CO. 1336 WILTON IA
— 563-735 not yet reported which blocks → MABEL COOP. TEL. CO. - IA 1424 BURR OAK IA
— 563-737 not yet reported which blocks → MABEL COOP. TEL. CO. - IA 1424 RIDGEWAY IA
— 563-742 0XXX1XXX which blocks → QWEST CORPORATION 9631 DAVENPORT IA
— 563-744 2XXX5XXX6XXX7XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 FARLEY IA
— 563-745 not yet reported which blocks → ACE TEL. ASSN. - MN 1345 SO CANTON IA

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.