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 425
ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 122
T-MOBILE USA, INC. 91
QWEST CORPORATION 69
LEVEL 3 COMMUNICATIONS, LLC - WA 49
NEW CINGULAR WIRELESS PCS, LLC 44
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
2006-10-04 425-457 0–9 XXXall 10 · 4 holders which blocks → QWEST CORPORATION 9638 BELLEVUE WA
2006-01-04 425-502 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 BELLEVUE WA
2005-08-31 425-383 0–9 XXXwhole prefix which blocks → QWEST CORPORATION 9638 BELLEVUE WA
2005-05-20 425-431 0–9 XXXwhole prefix which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 HALLS LAKE WA
2005-03-16 425-292 0–9 XXXall 10 · 4 holders which blocks → COMCAST IP PHONE, LLC 318J NORTH BEND WA
2005-03-16 425-549 0–9 XXXall 10 · 6 holders which blocks → COMCAST IP PHONE, LLC 318J CARNATION WA
2005-02-28 425-441 0–9 XXXall 10 · 5 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 FALL CITY WA
2004-09-16 425-256 0–9 XXXall 10 · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 BELLEVUE WA
2002-05-14 425-328 1XXX2XXX3XXX4XXX5XXX8XXX9XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 EVERETT WA
2002-03-07 425-533 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 BELLEVUE WA
2002-02-28 425-341 0XXX1XXX3XXX4XXX5XXX7XXX8XXX9XXX · 5 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 SILVERLAKE WA
2002-02-21 425-336 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 RENTON WA
2002-02-21 425-358 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 MAPLE VLY WA
2002-02-21 425-654 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 ISSAQUAH WA
2001-10-31 425-367 0–9 XXXall 10 · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 EVERETT WA
2001-10-22 425-361 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 HALLS LAKE WA
2001-10-11 425-518 none assigned yet which blocks → T-MOBILE USA, INC. 6529 BELLEVUE WA
2001-09-10 425-708 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 KIRKLAND WA
2001-08-15 425-301 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 BELLEVUE WA
2001-07-25 425-320 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 EVERETT WA
2001-05-30 425-242 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 KIRKLAND WA
2001-05-30 425-967 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 HALLS LAKE WA
2001-05-04 425-408 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 BOTHELL WA
2001-04-30 425-374 0XXX1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 EVERETT WA
2001-04-24 425-278 4XXX5XXX6XXX8XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BELLEVUE WA
2001-04-24 425-460 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BELLEVUE WA
2001-04-24 425-463 5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BELLEVUE WA
2001-04-23 425-519 9XXX which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 BELLEVUE WA
2001-04-23 425-586 0XXX which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 BELLEVUE WA
2001-04-23 425-943 0XXX1XXX9XXX · 2 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 BELLEVUE WA
2001-04-23 425-961 0XXX2XXX3XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 ISSAQUAH WA
2001-04-23 425-981 0XXX5XXX6XXX7XXX · 3 holders which blocks → TELEPORT COMMUNICATIONS AMERICA, LLC - WA 7146 RENTON WA
2001-04-16 425-343 not yet reported which blocks → T-MOBILE USA, INC. 6529 EVERETT WA
2001-04-16 425-344 not yet reported which blocks → T-MOBILE USA, INC. 6529 EVERETT WA
2001-04-16 425-737 not yet reported which blocks → T-MOBILE USA, INC. 6529 EVERETT WA
2001-04-16 425-770 not yet reported which blocks → T-MOBILE USA, INC. 6529 BOTHELL WA
2001-03-30 425-285 4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 KIRKLAND WA
2001-03-30 425-286 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 BOTHELL WA
2001-03-26 425-306 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RENTON WA
2001-03-20 425-329 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 HALLS LAKE WA
2001-03-20 425-919 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 RENTON WA
2001-02-28 425-395 0XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 ISSAQUAH WA
2001-02-15 425-200 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WA 5812 ISSAQUAH WA
2001-01-29 425-248 0XXX1XXX3XXX5XXX7XXX8XXX9XXX which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 HALLS LAKE WA
2001-01-24 425-275 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 HALLS LAKE WA
2001-01-24 425-293 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 EVERETT WA
2001-01-24 425-295 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 ISSAQUAH WA
— 425-201 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 BELLEVUE WA
— 425-202 4XXX5XXX6XXX7XXX · 3 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 KIRKLAND WA
— 425-203 not yet reported which blocks → QWEST CORPORATION 9638 RENTON WA

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.