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 509
LEVEL 3 COMMUNICATIONS, LLC - WA 32
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
2019-06-20 509-905 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 PASCO WA
2016-12-07 509-904 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 SPOKANE WA
2016-02-09 509-417 0XXX2XXX4XXX7XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 WARDEN WA
2015-01-15 509-903 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 LIBERTY LK WA
2004-06-14 509-320 0XXX2XXX3XXX4XXX7XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 STARBUCK WA
2003-01-07 509-203 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 GRANDVIEW WA
2002-10-18 509-383 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 GRANGER WA
2002-09-19 509-643 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 SUNNYSIDE WA
2002-09-11 509-978 1XXX2XXX3XXX4XXX6XXX7XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 NESPELEM WA
2002-09-11 509-983 7XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 STARBUCK WA
2002-07-17 509-855 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 MOSES LAKE WA
2002-06-12 509-774 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 WH SALMON WA
2002-06-12 509-776 6XXX7XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 COLUMBIA WA
2002-06-12 509-778 0–9 XXXall 10 · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 PROSSER WA
2002-05-07 509-590 0–9 XXXall 10 · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 SPOKANE WA
2002-05-07 509-591 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 KENNEWICK WA
2002-05-07 509-593 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 WALLAWALLA WA
2002-05-07 509-594 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 YAKIMA WA
2002-04-04 509-557 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 OMAK WA
2002-04-04 509-563 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 COLVILLE WA
2002-04-04 509-566 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 POMEROY WA
2002-03-14 509-587 0XXX1XXX2XXX4XXX6XXX7XXX8XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 BREWSTER WA
2002-02-07 509-288 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 COLFAX WA
— 509-293 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 WENATCHEE WA
— 509-388 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 YAKIMA WA
— 509-392 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 RICHLAND WA
— 509-396 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 KENNEWICK WA
— 509-416 0–9 XXXall 10 · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 PASCO WA
— 509-500 0XXX2XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 ASOTIN WA
— 509-715 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 PULLMAN WA
— 509-931 0–9 XXXall 10 · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 SPOKANE WA
— 509-980 1XXX2XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 CONNELL WA

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.