Recent prefix assignments

1 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, last 30 days — NPA 503
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
503-487 0–9 XXXall 10 · 6 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - OR 3234 NEWBERG OR
503-488 0XXX5XXX6XXX9XXX · 3 holders which blocks → LEVEL 3 TELECOM OF OREGON, LLC - OR 7537 PORTLAND OR
503-489 3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 GRESHAM OR
503-490 none assigned yet which blocks → T-MOBILE USA, INC. 6529 PORTLAND OR
503-491 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 GRESHAM OR
503-492 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 GRESHAM OR
503-493 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
503-494 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
503-495 not yet reported which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - OR 7531 BEAVERTON OR
503-496 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 CLACKAMAS OR
503-497 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
503-498 0XXX1XXX2XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - OR 7531 STFRD-SNDY OR
503-499 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
503-502 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OR 5820 PORTLAND OR
503-504 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OR 5820 PORTLAND OR
503-506 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - OR 7531 STFRD-SNDY OR
503-507 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OR 5820 SALEM OR
503-508 8XXX9XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SALEM OR
503-510 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SALEM OR
503-511 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX OR
503-512 0XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 TELECOM OF OREGON, LLC - OR 7537 GRESHAM OR
503-513 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
503-514 not yet reported which blocks → SPOK, INC. 6630 PORTLAND OR
503-515 not yet reported which blocks → T-MOBILE USA, INC. 6529 PORTLAND OR
503-516 not yet reported which blocks → T-MOBILE USA, INC. 6529 PORTLAND OR
503-517 not yet reported which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 PORTLAND OR
503-518 not yet reported which blocks → BEAVER CREEK COOPERATIVE TELEPHONE COMPANY - OR 461J CLACKAMAS OR
503-519 none assigned yet which blocks → T-MOBILE USA, INC. 6529 PORTLAND OR
503-520 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
503-521 6XXX7XXX · 2 holders which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
503-522 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OR 5820 PORTLAND OR
503-523 3XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - OR 3234 BEAVERTON OR
503-524 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
503-525 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
503-526 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
503-527 not yet reported which blocks → SPOK, INC. 6630 PORTLAND OR
503-528 4XXX6XXX which blocks → QWEST CORPORATION 9638 PORTLAND OR
503-529 not yet reported which blocks → SPOK, INC. 6630 PORTLAND OR
503-530 0XXX6XXX9XXX which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - OR 7531 BEAVERTON OR
503-531 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
503-532 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BEAVERTON OR
503-533 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
503-534 6XXX which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
503-535 9XXX which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - OR 7531 PORTLAND OR
503-536 3XXX5XXX which blocks → LEVEL 3 COMMUNICATIONS, LLC - OR 3234 BEAVERTON OR
503-537 none assigned yet which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 NEWBERG OR
503-538 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 NEWBERG OR
503-539 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 PORTLAND OR
503-540 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
503-541 not yet reported which blocks → OR

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.