NumberResearch Membership · Data 10/01/2026

Recent prefix assignments

374 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 10/01/2026

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
Rogers Communications Canada Inc. (Wireless) 46
8X8, INC. 43
NEW CINGULAR WIRELESS PCS, LLC - DC 28
NEW CINGULAR WIRELESS PCS, LLC - IL 23
ONVOY, LLC - CA 19
New assignments by month Oct 2026 Sep 2026 Aug 2026 Jul 2026 Jun 2026 May 2026 Apr 2026 Mar 2026 Feb 2026 Jan 2026 Dec 2025 Nov 2025
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Quick find in this area code:
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 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
— 503-542 7XXX8XXX which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 PORTLAND OR
— 503-543 1XXX which blocks → CENTURYTEL OF OREGON, INC. DBA CENTURYLINK 2395 SCAPPOOSE OR
— 503-544 not yet reported which blocks → T-MOBILE USA, INC. 6529 PORTLAND OR
— 503-546 not yet reported which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 PORTLAND OR
— 503-547 3XXX4XXX5XXX7XXX9XXX which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
— 503-548 3XXX4XXX7XXX8XXX · 2 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 PORTLAND OR
— 503-549 0XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - OR 3234 BEAVERTON OR
— 503-550 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 NEWBERG OR
— 503-551 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SALEM OR
— 503-552 not yet reported which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-553 9XXX which blocks → QWEST CORPORATION 9638 PORTLAND OR
— 503-554 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 NEWBERG OR
— 503-555 not yet reported which blocks → MULTIPLE OCN LISTING MULT DIR ASST OR
— 503-556 not yet reported which blocks → QWEST CORPORATION 9638 RAINIER OR
— 503-557 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-558 2XXX3XXX4XXX5XXX6XXX7XXX · 2 holders which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 STFRD-SNDY OR
— 503-559 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SALEM OR
— 503-560 8XXX9XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 MCMINNVL OR
— 503-561 not yet reported which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 SALEM OR
— 503-563 0XXX2XXX3XXX5XXX6XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - OR 3234 STFRD-SNDY OR
— 503-565 0XXX1XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → ONVOY, LLC - OR 750E MCMINNVL OR
— 503-566 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-569 2XXX8XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 SALEM OR
— 503-570 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 STFRD-SNDY OR
— 503-571 not yet reported which blocks → QWEST CORPORATION 9638 CLACKAMAS OR
— 503-572 none assigned yet which blocks → T-MOBILE USA, INC. 6529 PORTLAND OR
— 503-573 0XXX1XXX3XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - OR 3234 GRESHAM OR
— 503-574 0XXX which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
— 503-576 0XXX1XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-577 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - OR 5820 PORTLAND OR
— 503-578 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
— 503-579 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR
— 503-580 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SALEM OR
— 503-581 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-582 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 STFRD-SNDY OR
— 503-584 1XXX which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-585 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-586 3XXX4XXX6XXX8XXX9XXX · 2 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7172 SALEM OR
— 503-587 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-588 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-589 not yet reported which blocks → QWEST CORPORATION 9638 SALEM OR
— 503-590 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4323 BEAVERTON OR

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 10/01/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.