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
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 301-462 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 2 holders which blocks → METROPCS, INC. 5562 MYERSVILLE MD
— 301-463 0XXX1XXX4XXX7XXX8XXX9XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 LONACONING MD
— 301-464 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z14 MD
— 301-465 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 MYERSVILLE MD
— 301-466 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-467 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-468 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNGTNZN11 MD
— 301-469 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-470 0XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z14 MD
— 301-471 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 FREDERICK MD
— 301-472 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 MECHANCSVL MD
— 301-473 0XXX1XXX2XXX3XXX6XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 FREDERICK MD
— 301-474 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-475 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LEONARDTN MD
— 301-476 0XXX1XXX3XXX4XXX5XXX6XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 ASHTON236 MD
— 301-477 0XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → COMCAST IP PHONE, LLC 318J WSNG236Z13 MD
— 301-478 0XXX1XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 FLINTSTONE MD
— 301-479 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSNG236Z13 MD
— 301-480 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-481 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 LEONARDTN MD
— 301-482 4XXX5XXX7XXX8XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 DAMASCS236 MD
— 301-483 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LAUREL236 MD
— 301-484 not yet reported which blocks → COMCAST IP PHONE, LLC 318J WSHNGTNZN4 MD
— 301-485 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → COMCAST IP PHONE, LLC 318J WSHNGTNZN6 MD
— 301-486 5XXX8XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-487 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 MYERSVILLE MD
— 301-488 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-489 2XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-490 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LAUREL236 MD
— 301-491 none assigned yet which blocks → USCOC OF CUMBERLAND, INC. DBA UNITED STATES CEL MD 4720 HAGERSTOWN MD
— 301-492 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-493 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-494 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 WSNG238Z15 MD
— 301-495 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN3 MD
— 301-496 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN2 MD
— 301-497 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LAUREL236 MD
— 301-498 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 LAUREL236 MD
— 301-499 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN5 MD
— 301-500 0–9 XXXall 10 · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 WSHNGTNZN2 MD
— 301-501 3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 OAKLAND MD
— 301-502 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-503 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 WSHNGTNZN2 MD
— 301-504 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN3 MD
— 301-505 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WSHNGTNZN6 MD
— 301-506 not yet reported which blocks → SPOK, INC. 6630 WSNG236Z13 MD
— 301-507 0XXX1XXX2XXX3XXX4XXX7XXX8XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 WSNG236Z13 MD
— 301-508 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 MYERSVILLE MD
— 301-509 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WSHNGTNZN3 MD
— 301-510 not yet reported which blocks → SPOK, INC. 6630 WSNG236Z13 MD
— 301-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX 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.