NumberResearch Membership · Data 09/21/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/21/2026

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 541
UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 27
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
— 541-296 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 THE DALLES OR
— 541-298 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 THE DALLES OR
— 541-308 4XXX which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 HOOD RIVER OR
— 541-333 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 GRASS VLY OR
— 541-352 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 PARKDALE OR
— 541-354 7XXX8XXX · 2 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 ODELL OR
— 541-374 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 CASCADELKS OR
— 541-386 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 HOOD RIVER OR
— 541-387 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 HOOD RIVER OR
— 541-442 1XXX2XXX4XXX7XXX · 3 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 WASCO OR
— 541-454 1XXX4XXX7XXX8XXX9XXX · 4 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 ARLINGTON OR
— 541-478 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 MOSIER OR
— 541-506 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 THE DALLES OR
— 541-557 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 LINCOLN CY OR
— 541-560 5XXX6XXX7XXX · 3 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 PROSPECT OR
— 541-565 4XXX6XXX7XXX9XXX · 3 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 MORO OR
— 541-594 4XXX7XXX · 2 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 CRATERLAKE OR
— 541-739 7XXX which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 RUFUS OR
— 541-793 4XXX5XXX · 2 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 DIAMOND LK OR
— 541-826 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 WHITE CITY OR
— 541-830 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 WHITE CITY OR
— 541-831 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 WHITE CITY OR
— 541-865 1XXX6XXX8XXX · 2 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 BUTTEFALLS OR
— 541-878 6XXX which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 SHADY COVE OR
— 541-949 1XXX2XXX7XXX · 3 holders which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 FISH LAKE OR
— 541-994 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 LINCOLN CY OR
— 541-996 not yet reported which blocks → UNITED TELEPHONE - NORTHWEST DBA CENTURYLINK - OR 4520 LINCOLN CY OR

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/21/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.