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
— 301-948 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-949 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-950 not yet reported which blocks → MD
— 301-951 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-952 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z15 MD
— 301-953 4XXX5XXX6XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-954 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN4 MD
— 301-955 2XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN4 MD
— 301-957 0XXX1XXX4XXX5XXX6XXX8XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 LAUREL236 MD
— 301-958 not yet reported which blocks → MD
— 301-959 not yet reported which blocks → MD
— 301-960 3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN3 MD
— 301-961 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-962 2XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-963 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 GAITHERSBG MD
— 301-964 8XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 MYERSVILLE MD
— 301-965 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN6 MD
— 301-966 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSNGTNZN12 MD
— 301-967 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-968 3XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN2 MD
— 301-970 0XXX1XXX3XXX4XXX6XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 WSNG238Z14 MD
— 301-971 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 7 holders which blocks → STARPOWER COMMUNICATIONS, LLC - MD 8832 WSHNGTNZN6 MD
— 301-972 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 GAITHERSBG MD
— 301-973 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F WSNG238Z14 MD
— 301-974 1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 2 holders which blocks → STARPOWER COMMUNICATIONS, LLC - MD 8832 LAUREL236 MD
— 301-975 7XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-976 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX MD
— 301-977 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 GAITHERSBG MD
— 301-978 0XXX1XXX3XXX6XXX7XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-979 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 WSNGTNZN10 MD
— 301-980 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-981 not yet reported which blocks → LEVEL 3 TELECOM OF MARYLAND, LLC - MD 7591 WSHNGTNZN5 MD
— 301-982 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-983 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN10 MD
— 301-984 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-985 2XXX which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN4 MD
— 301-986 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-987 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 GAITHERSBG MD
— 301-988 none assigned yet which blocks → USCOC OF CUMBERLAND, INC. DBA UNITED STATES CEL MD 4720 HAGERSTOWN MD
— 301-989 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN12 MD
— 301-990 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 GAITHERSBG MD
— 301-991 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 HAGERSTOWN MD
— 301-992 none assigned yet which blocks → METROPCS, INC. 5562 HAGERSTOWN MD
— 301-993 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-994 4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 LXTNPKGRML MD
— 301-995 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LXTNPKGRML MD
— 301-996 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 WSHNGTNZN3 MD
— 301-997 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 LEONARDTN MD
— 301-998 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-999 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 HAGERSTOWN 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.