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 301
VERIZON MARYLAND, INC. 465
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 51
NEW CINGULAR WIRELESS PCS, LLC - DC 47
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 40
TELEPORT COMMUNICATIONS AMERICA, LLC - DC 31
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
— 301-785 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-786 0XXX1XXX2XXX3XXX5XXX6XXX8XXX · 6 holders which blocks → VERIZON MARYLAND, INC. 9212 MCCOOLE MD
— 301-787 9XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-788 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 FREDERICK MD
— 301-790 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-791 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-792 not yet reported which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 WSHNGTNZN3 MD
— 301-793 not yet reported which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 WSHNGTNZN3 MD
— 301-794 2XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z14 MD
— 301-795 4XXX5XXX8XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSNGTNZN10 MD
— 301-797 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-798 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 DAMASCS240 MD
— 301-800 0–9 XXXall 10 · 4 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 HAGERSTOWN MD
— 301-801 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-802 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-803 0XXX5XXX8XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-804 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ASHTON236 MD
— 301-805 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z14 MD
— 301-806 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 WSHNGTNZN3 MD
— 301-807 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-808 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-809 7XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z14 MD
— 301-810 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → ONVOY SPECTRUM, LLC 624H BUCKEYSTN MD
— 301-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MD
— 301-812 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 WSNG238Z15 MD
— 301-813 not yet reported which blocks → BALTIMORE-WASHINGTON TELEPHONE (BWT) 8697 WSHNGTNZN2 MD
— 301-814 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 WSHNGTNZN2 MD
— 301-815 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 FREDERICK MD
— 301-816 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-817 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-818 not yet reported which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F WALDORF MD
— 301-819 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN3 MD
— 301-820 0XXX1XXX2XXX3XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 GAITHERSBG MD
— 301-821 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 LAUREL236 MD
— 301-822 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSNGTNZN11 MD
— 301-823 0–9 XXXall 10 · 7 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 WSNG236Z13 MD
— 301-824 0XXX8XXX9XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 SMITHSBURG MD
— 301-825 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → AT&T - LOCAL 7421 WSNGTNZN10 MD
— 301-826 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LXTNPKGRML MD
— 301-827 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-828 0XXX1XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 WSHNGTNZN2 MD
— 301-829 7XXX which blocks → VERIZON MARYLAND, INC. 9212 MOUNT AIRY MD
— 301-830 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - MD 7325 WSHNGTNZN3 MD
— 301-831 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 DAMASCS240 MD
— 301-832 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 WSHNGTNZN4 MD
— 301-833 0–9 XXXall 10 · 2 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 WSNG236Z14 MD
— 301-834 0XXX1XXX2XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 BRUNSWICK MD
— 301-836 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 8 holders which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-837 4XXX6XXX7XXX8XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSNG236Z13 MD
— 301-838 1XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD

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.