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
— 641-205 2XXX4XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → LOCAL TELEPHONE DATA SERVICES CORP. 2842 KNOXVILLE IA
— 641-209 2XXX which blocks → LOCAL TELEPHONE DATA SERVICES CORP. 2842 FAIRFIELD IA
— 641-211 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IA
— 641-215 0–9 XXXall 10 · 5 holders which blocks → TELNYX LLC 073H OSKALOOSA IA
— 641-216 0–9 XXXall 10 · 10 holders which blocks → UNITED STATES CELLULAR - IA 6266 CENTERVL IA
— 641-217 0–9 XXXall 10 · 9 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 CHARITON IA
— 641-218 0–9 XXXall 10 · 6 holders which blocks → UNITED STATES CELLULAR - IA 6266 KNOXVILLE IA
— 641-220 8XXX9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 CHARLES CY IA
— 641-223 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 OSCEOLA IA
— 641-227 not yet reported which blocks → PARTNER COMMUNICATIONS COOPERATIVE 1187 BAXTER IA
— 641-228 0XXX which blocks → QWEST CORPORATION 9631 CHARLES CY IA
— 641-236 not yet reported which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 GRINNELL IA
— 641-238 0XXX1XXX3XXX4XXX5XXX6XXX9XXX · 4 holders which blocks → ONVOY, LLC - IA 221F GENEVA IA
— 641-257 7XXX8XXX9XXX which blocks → QWEST CORPORATION 9631 CHARLES CY IA
— 641-259 4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 MONROE IA
— 641-260 2XXX3XXX4XXX5XXX8XXX9XXX · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 6570 GRINNELL IA
— 641-269 not yet reported which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 GRINNELL IA
— 641-293 not yet reported which blocks → WINNEBAGO COOP. TEL. ASSN. - IA 1337 SO EMMONS IA
— 641-297 not yet reported which blocks → FMTC-I35, INC. D/B/A OMNITEL COMMUNICATIONS 1209 ST MARYS IA
— 641-298 4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 1123 AMUND IA
— 641-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IA
— 641-312 not yet reported which blocks → IA
— 641-315 1XXX4XXX5XXX · 3 holders which blocks → OMNITEL COMMUNICATIONS, INC. - IA 3620 MARBLEROCK IA
— 641-318 not yet reported which blocks → T-MOBILE USA, INC. 6529 KNOXVILLE IA
— 641-319 not yet reported which blocks → IA
— 641-322 1XXX2XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER COMMUNICATIONS OF IOWA, INC. 1127 CORNING IA
— 641-324 5XXX6XXX7XXX8XXX · 3 holders which blocks → QWEST CORPORATION 9631 NORTHWOOD IA
— 641-325 1XXX2XXX3XXX4XXX5XXX7XXX · 4 holders which blocks → UNITED STATES CELLULAR - IA 6266 GRINNELL IA
— 641-326 3XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 1123 MONA IA
— 641-329 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 1123 BAILEY IA
— 641-330 none assigned yet which blocks → UNITED STATES CELLULAR - IA 6266 CHARLES CY IA
— 641-333 not yet reported which blocks → FRONTIER COMMUNICATIONS OF IOWA, INC. 1127 LENOX IA
— 641-335 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 PRESCOTT IA
— 641-336 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 CLEARFIELD IA
— 641-337 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 ORIENT IA
— 641-338 8XXX which blocks → GRAND RIVER MUTUAL TEL CO 1888 THAYER IA
— 641-339 3XXX4XXX5XXX6XXX7XXX9XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 SHANNON CY IA
— 641-340 not yet reported which blocks → IOWA RSA 2 LIMITED PARTNERSHIP DBA CHAT MOBILITY 9572 OSCEOLA IA
— 641-342 not yet reported which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 OSCEOLA IA
— 641-343 2XXX8XXX · 2 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 GREENFIELD IA
— 641-344 none assigned yet which blocks → UNITED STATES CELLULAR - IA 6266 CRESTON IA
— 641-345 not yet reported which blocks → COON VALLEY COOP. TEL. ASSN., INC. 1137 NEVINVILLE IA
— 641-346 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 ARISPE IA
— 641-347 0XXX2XXX3XXX4XXX6XXX7XXX9XXX · 6 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. 1178 AFTON IA
— 641-348 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - NORTH 1167 KENT IA
— 641-349 not yet reported which blocks → FRONTIER COMMUNICATIONS OF IOWA, INC. 1127 SHARPSBURG IA
— 641-355 3XXX which blocks → CLEAR LAKE INDEPENDENT TEL. CO. 1132 CLEAR LAKE IA
— 641-357 not yet reported which blocks → CLEAR LAKE INDEPENDENT TEL. CO. 1132 CLEAR LAKE IA
— 641-358 not yet reported which blocks → FRONTIER COMMUNICATIONS OF IOWA, INC. 1127 MESERVEY IA
— 641-363 0XXX2XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → WINDSTREAM IOWA COMMUNICATIONS, INC. - SYSTEMS 1170 MINGO 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.