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 860
SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 325
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 63
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 60
TELEPORT COMMUNICATIONS AMERICA, LLC - CT 56
PAETEC ITEL, LLC 50
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
— 860-306 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 HARTFORD CT
— 860-307 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 HARWINTON CT
— 860-308 0XXX1XXX2XXX3XXX4XXX5XXX6XXX9XXX · 5 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 HARTFORD CT
— 860-309 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 HARWINTON CT
— 860-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 860-312 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NORWICH CT
— 860-313 8XXX9XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 HARTFORD CT
— 860-314 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 BRISTOL CT
— 860-315 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 PUTNAM CT
— 860-316 0–9 XXXall 10 · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 MIDDLETOWN CT
— 860-317 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 PLAINFIELD CT
— 860-318 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CORNWALL CT
— 860-319 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 NORWICH CT
— 860-320 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 HARTFORD CT
— 860-321 0XXX1XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 FARMINGTON CT
— 860-322 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 DEEP RIVER CT
— 860-323 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 9 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SIMSBURY CT
— 860-325 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SIMSBURY CT
— 860-326 0XXX1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CT 7143 NEW LONDON CT
— 860-327 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 MANCHESTER CT
— 860-329 0–9 XXXall 10 · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SOUTHINGTN CT
— 860-330 not yet reported which blocks → SPOK, INC. 6630 HARTFORD CT
— 860-331 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 HARTFORD CT
— 860-332 not yet reported which blocks → SPOK, INC. 6630 HARTFORD CT
— 860-333 0–9 XXXall 10 · 6 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW LONDON CT
— 860-334 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 NORWICH CT
— 860-335 0–9 XXXall 10 · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 HARTFORD CT
— 860-336 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - CT 7143 WILLIMNTIC CT
— 860-337 0–9 XXXall 10 · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 COLUMBIA CT
— 860-338 2XXX5XXX6XXX7XXX8XXX9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 GLASTONBY CT
— 860-339 0–9 XXXall 10 · 9 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 OLD SAYBRK CT
— 860-340 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 HARTFORD CT
— 860-341 0XXX1XXX2XXX3XXX4XXX5XXX6XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 STORRS CT
— 860-342 8XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-343 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-344 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-345 1XXX5XXX6XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 HADDAM CT
— 860-346 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-347 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-348 3XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEWBRITAIN CT
— 860-349 4XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-350 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEWMILFORD CT
— 860-351 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 PLAINVILLE CT
— 860-352 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CANTON CT
— 860-354 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEWMILFORD CT
— 860-355 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEWMILFORD CT
— 860-356 0–9 XXXall 10 · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 NEWBRITAIN CT
— 860-357 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 NEWBRITAIN CT
— 860-358 0XXX9XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MIDDLETOWN CT
— 860-359 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 COLUMBIA CT

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.