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 203
SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 338
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 61
NEW CINGULAR WIRELESS PCS, LLC - DC 52
OMNIPOINT COMMUNICATIONS, INC. - CT 47
LEVEL 3 COMMUNICATIONS, LLC - CT 41
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
— 203-686 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MERIDEN CT
— 203-687 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 NEW HAVEN CT
— 203-688 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN CT
— 203-689 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → AT&T - LOCAL 7421 GUILFORD CT
— 203-691 0XXX1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN CT
— 203-692 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 FAIRFIELD CT
— 203-694 0XXX1XXX2XXX3XXX4XXX9XXX · 4 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 MERIDEN CT
— 203-695 4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 WATERBURY CT
— 203-696 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 BRIDGEPORT CT
— 203-697 5XXX7XXX8XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 WALLINGFD CT
— 203-698 5XXX6XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 OLDGRNWICH CT
— 203-699 6XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 CHESHIRE CT
— 203-700 not yet reported which blocks → CT
— 203-701 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → AT&T - LOCAL 7421 MILFORD CT
— 203-702 3XXX which blocks → PAETEC ITEL, LLC 829J DANBURY CT
— 203-703 0XXX1XXX2XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 STAMFORD CT
— 203-705 1XXX7XXX8XXX9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 7230 STAMFORD CT
— 203-708 1XXX7XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 STAMFORD CT
— 203-709 0XXX1XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 WATERBURY CT
— 203-710 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 NEW HAVEN CT
— 203-711 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX CT
— 203-712 0XXX1XXX6XXX7XXX8XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 HUNTINGTON CT
— 203-713 0–9 XXXall 10 · 6 holders which blocks → ONVOY, LLC - CT 639C MILFORD CT
— 203-714 0–9 XXXall 10 · 7 holders which blocks → ONVOY SPECTRUM, LLC 624H NAUGATUCK CT
— 203-715 8XXX which blocks → OMNIPOINT COMMUNICATIONS, INC. - CT 6624 MERIDEN CT
— 203-716 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 NEW CANAAN CT
— 203-718 0XXX1XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - CT 4800 CHESHIRE CT
— 203-719 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 7230 STAMFORD CT
— 203-720 6XXX8XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NAUGATUCK CT
— 203-721 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 WATERBURY CT
— 203-722 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 NORWALK CT
— 203-723 3XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NAUGATUCK CT
— 203-724 5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J STAMFORD CT
— 203-725 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → COMCAST IP PHONE, LLC 318J WATERBURY CT
— 203-729 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NAUGATUCK CT
— 203-730 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 DANBURY CT
— 203-731 0XXX9XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 DANBURY CT
— 203-732 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 ANSONIDRBY CT
— 203-733 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 6388 DANBURY CT
— 203-734 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 ANSONIDRBY CT
— 203-735 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 ANSONIDRBY CT
— 203-736 7XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 ANSONIDRBY CT
— 203-737 0XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN CT
— 203-738 5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J GUILFORD CT
— 203-739 5XXX9XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 DANBURY CT
— 203-740 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 DANBURY CT
— 203-741 8XXX9XXX · 2 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 WALLINGFD CT
— 203-743 not yet reported which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 DANBURY CT
— 203-744 9XXX which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 DANBURY CT
— 203-745 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 9147 NEW HAVEN 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.