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 574
LEVEL 3 COMMUNICATIONS, LLC - IN 26
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
2006-03-03 574-878 7XXX8XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 NO WEBSTER IN
2005-09-22 574-696 1XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 MILFORD IN
2005-02-15 574-330 1XXX3XXX4XXX5XXX7XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 MILLERSBG IN
2005-02-15 574-797 1XXX3XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 NEWCARLISL IN
2005-01-06 574-655 5XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 FLORA IN
2004-04-29 574-313 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 FLORA IN
2004-04-06 574-325 0XXX1XXX2XXX3XXX5XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 SYRACUSE IN
2002-07-23 574-205 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 WINAMAC IN
2002-07-23 574-207 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 9 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 KNOX IN
2002-07-23 574-230 1XXX3XXX4XXX5XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 KEWANNA IN
2002-07-23 574-253 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 LEESBURG IN
2002-07-23 574-279 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 WALKERTON IN
2002-07-23 574-281 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 ARGOS IN
2002-07-23 574-285 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 NAPPANEE IN
2002-07-23 574-331 1XXX2XXX3XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 BREMEN IN
2002-06-04 574-203 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 LAPAZ IN
2002-06-04 574-212 1XXX2XXX3XXX4XXX7XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 MONTEREY IN
2002-06-04 574-228 0XXX1XXX3XXX4XXX5XXX7XXX8XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 BURNETTSVL IN
2002-06-04 574-241 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 NO JUDSON IN
2002-06-04 574-244 1XXX2XXX3XXX6XXX7XXX8XXX · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 NO WEBSTER IN
2002-05-23 574-217 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 SOUTH BEND IN
2002-05-13 574-914 1XXX2XXX3XXX4XXX5XXX6XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 PLYMOUTH IN
2002-05-10 574-263 1XXX2XXX3XXX4XXX5XXX6XXX8XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 TIPPECANOE IN
2002-05-10 574-306 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 WARSAW IN
2002-05-10 574-907 4XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 MILLWOOD IN
— 574-807 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IN 4803 SOUTH BEND IN

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.