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 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
— 301-729 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 CUMBERLAND MD
— 301-730 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 MYERSVILLE MD
— 301-731 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN4 MD
— 301-732 0–9 XXXall 10 · 5 holders which blocks → METROPCS, INC. 5562 FREDERICK MD
— 301-733 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-734 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN3 MD
— 301-735 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-736 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-737 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LXTNPKGRML MD
— 301-738 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-739 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-741 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 LAUREL236 MD
— 301-742 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 WSHNGTNZN2 MD
— 301-743 0XXX1XXX which blocks → VERIZON MARYLAND, INC. 9212 INDIANHEAD MD
— 301-744 0XXX7XXX8XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 INDIANHEAD MD
— 301-745 2XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-746 0XXX1XXX2XXX3XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 FRIENDSVL MD
— 301-747 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - DC 7529 WSHNGTNZN6 MD
— 301-748 none assigned yet which blocks → METROPCS, INC. 5562 FREDERICK MD
— 301-749 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN6 MD
— 301-751 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WALDORF MD
— 301-752 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WALDORF MD
— 301-753 0XXX3XXX7XXX8XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN6 MD
— 301-754 6XXX which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN3 MD
— 301-755 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN3 MD
— 301-756 1XXX2XXX5XXX6XXX · 4 holders which blocks → LEVEL 3 TELECOM OF MARYLAND, LLC - MD 7591 WSNG236Z14 MD
— 301-757 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LXTNPKGRML MD
— 301-758 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-759 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 CUMBERLAND MD
— 301-762 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-763 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-764 0XXX3XXX4XXX8XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 WALDORF MD
— 301-765 4XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-766 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN MD
— 301-767 5XXX6XXX7XXX which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-769 0XXX1XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 LEONARDTN MD
— 301-770 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-771 0XXX1XXX9XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-772 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN4 MD
— 301-773 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN4 MD
— 301-774 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ASHTON236 MD
— 301-775 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-776 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LAUREL236 MD
— 301-777 6XXX which blocks → VERIZON MARYLAND, INC. 9212 CUMBERLAND MD
— 301-778 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN5 MD
— 301-779 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN4 MD
— 301-780 4XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z15 MD
— 301-782 0XXX8XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 BRANDYWINE MD
— 301-783 not yet reported which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F CUMBERLAND MD
— 301-784 9XXX which blocks → VERIZON MARYLAND, INC. 9212 CUMBERLAND MD

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.