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 443
PAETEC ITEL, LLC 153
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 121
OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 94
NEW CINGULAR WIRELESS PCS, LLC - DC 71
LEVEL 3 COMMUNICATIONS, LLC - MD 69
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
2023-11-21 443-443 0–9 XXXall 10 · 2 holders which blocks → COMMIO, LLC 939H ARBUTUS MD
2023-05-16 443-667 0–9 XXXall 10 · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 DELMAR MD
2018-11-19 443-774 0–9 XXXall 10 · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 COLUMBIA MD
2017-02-23 443-936 0–9 XXXall 10 · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ELKRIDGE MD
2015-01-21 443-819 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BEL AIR MD
2014-12-23 443-961 0–9 XXXall 10 · 3 holders which blocks → INTRADO COMMUNICATIONS, LLC 820C BALTIMORE MD
2014-10-08 443-775 0–9 XXXall 10 · 7 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 ANNAPOLIS MD
2014-06-13 443-809 0–9 XXXwhole prefix which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 TOWSON MD
2014-04-04 443-808 0–9 XXXall 10 · 4 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F ANNAPOLIS MD
2014-01-17 443-776 0–9 XXXall 10 · 7 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F ELKRIDGE MD
2013-06-21 443-410 0–9 XXXall 10 · 5 holders which blocks → CENTURYLINK COMMUNICATIONS, LLC 508J GLENBURNIE MD
2013-01-21 443-836 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BALTIMORE MD
2012-11-27 443-720 0–9 XXXall 10 · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 ABERDEEN MD
2012-09-20 443-906 0–9 XXXall 10 · 5 holders which blocks → PEERLESS NETWORK OF MARYLAND, LLC 568G SEVERNA PK MD
2012-09-19 443-713 0–9 XXXall 10 · 3 holders which blocks → PEERLESS NETWORK OF MARYLAND, LLC 568G GLENBURNIE MD
2012-05-23 443-666 0–9 XXXall 10 · 9 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - MD 6119 CHESTERTN MD
2012-05-23 443-900 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 TOWSON MD
2012-04-05 443-301 0–9 XXXall 10 · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 BALTIMORE MD
2012-01-27 443-240 0–9 XXXwhole prefix which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 BALTIMORE MD
2012-01-09 443-202 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BALTIMORE MD
2011-12-06 443-571 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BALTIMORE MD
2011-12-01 443-991 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 TOWSON MD
2011-11-21 443-970 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BALTIMORE MD
2011-11-21 443-972 0–9 XXXall 10 · 8 holders which blocks → PAETEC ITEL, LLC 829J CAMBRIDGE MD
2011-11-21 443-978 0–9 XXXall 10 · 7 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 SALISBURY MD
2011-11-21 443-979 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 COLUMBIA MD
2011-11-21 443-981 0–9 XXXall 10 · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 FALLSTON MD
2011-11-09 443-634 0–9 XXXwhole prefix which blocks → VERIZON MARYLAND, INC. 9212 WATERLO236 MD
2011-10-24 443-931 0–9 XXXall 10 · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 7228 BALTIMORE MD
2011-10-17 443-401 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BALTIMORE MD
2011-10-11 443-214 0–9 XXXall 10 · 6 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ANNAPOLIS MD
2011-10-07 443-862 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 TOWSON MD
2011-10-07 443-917 0–9 XXXall 10 · 8 holders which blocks → ONVOY, LLC - MD 876D COLUMBIA MD
2011-10-07 443-960 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 GLENBURNIE MD
2011-10-06 443-723 0–9 XXXall 10 · 2 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
2011-10-06 443-726 0–9 XXXall 10 · 3 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
2011-09-30 443-210 0–9 XXXall 10 · 6 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 SALISBURY MD
2011-09-07 443-903 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BEL AIR MD
2011-09-07 443-915 0–9 XXXwhole prefix which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BALTIMORE MD
2011-09-07 443-941 0–9 XXXall 10 · 8 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ELKTON MD
2011-09-07 443-952 0–9 XXXall 10 · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 WESTMINSTR MD
2011-09-07 443-953 0–9 XXXall 10 · 3 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 SALISBURY MD
2011-08-25 443-580 0–9 XXXall 10 · 2 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
2011-08-22 443-916 0–9 XXXall 10 · 2 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
2011-08-22 443-932 0–9 XXXall 10 · 2 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
2011-08-22 443-948 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE MD
2011-08-11 443-892 0–9 XXXall 10 · 5 holders which blocks → BANDWIDTH.COM CLEC, LLC - MD 071F NEWWINDSOR MD
2011-08-10 443-699 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 ANNAPOLIS MD
2011-08-10 443-890 0–9 XXXall 10 · 2 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 6395 BALTIMORE MD
2011-07-18 443-560 0–9 XXXall 10 · 2 holders which blocks → OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 6855 BALTIMORE 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.