NumberResearch Membership · Data 09/19/2026

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 509
NEW CINGULAR WIRELESS PCS, LLC 1
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
— 509-290 5XXX6XXX7XXX8XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 SPOKANE WA
— 509-291 8XXX9XXX · 2 holders which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 ROCKFORD WA
— 509-292 4XXX6XXX · 2 holders which blocks → QWEST CORPORATION 9638 ELK-GRNBLF WA
— 509-293 0–9 XXXall 10 · 3 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - WA 6121 WENATCHEE WA
— 509-295 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 CLARKSTON WA
— 509-297 2XXX3XXX7XXX8XXX · 2 holders which blocks → CENTURYTEL OF WASHINGTON, INC. DBA CENTURYLINK 2408 MATHEWSCOR WA
— 509-299 0XXX8XXX9XXX · 2 holders which blocks → CENTURYTEL OF WASHINGTON, INC. DBA CENTURYLINK 2408 MEDICAL LK WA
— 509-300 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC - WA 483E WENATCHEE WA
— 509-301 none assigned yet which blocks → METROPCS, INC. 5562 WALLAWALLA WA
— 509-302 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → METROPCS, INC. 5562 PASCO WA
— 509-303 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → T-MOBILE USA, INC. 6529 PROSSER WA
— 509-304 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 CLE ELUM WA
— 509-305 2XXX3XXX4XXX5XXX6XXX7XXX8XXX which blocks → T-MOBILE USA, INC. 6529 SUNNYSIDE WA
— 509-306 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → METROPCS, INC. 5562 ELLENSBURG WA
— 509-307 none assigned yet which blocks → T-MOBILE USA, INC. 6529 YAKIMA WA
— 509-308 none assigned yet which blocks → T-MOBILE USA, INC. 6529 KENNEWICK WA
— 509-310 1XXX2XXX3XXX7XXX8XXX · 4 holders which blocks → T-MOBILE USA, INC. 6529 WH SALMON WA
— 509-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX WA
— 509-314 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WA 5812 TOPPENISH WA
— 509-321 3XXX4XXX6XXX7XXX · 3 holders which blocks → ELECTRIC LIGHTWAVE LLC DBA ALLSTREAM 7173 SPOKANE WA
— 509-322 9XXX which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 OMAK WA
— 509-323 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-324 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-325 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-326 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-327 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-328 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-329 6XXX8XXX · 2 holders which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-331 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → QWEST CORPORATION 9638 OTHELLO WA
— 509-332 none assigned yet which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-333 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-334 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-335 not yet reported which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-336 8XXX9XXX · 2 holders which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-337 2XXX3XXX4XXX5XXX · 4 holders which blocks → QWEST CORPORATION 9638 WAITSBURG WA
— 509-338 5XXX7XXX8XXX · 3 holders which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-339 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → ZIPLY FIBER NORTHWEST, LLC DBA ZIPLY FIBER 4324 PULLMAN WA
— 509-340 5XXX9XXX · 2 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SPOKANE WA
— 509-341 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC 6010 TWISP WA
— 509-342 2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → T-MOBILE USA, INC. 6529 SPOKANE WA
— 509-343 not yet reported which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SPOKANE WA
— 509-344 9XXX which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC 7229 SPOKANE WA
— 509-345 1XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → CENTURYTEL OF WASHINGTON, INC. DBA CENTURYLINK 2408 WILSON CRK WA
— 509-346 0XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → CENTURYTEL OF WASHINGTON, INC. DBA CENTURYLINK 2408 OTHELLO WA
— 509-349 3XXX4XXX5XXX6XXX · 4 holders which blocks → QWEST CORPORATION 9638 WARDEN WA
— 509-350 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → METROPCS, INC. 5562 MOSES LAKE WA
— 509-351 not yet reported which blocks → ONVOY, LLC - WA 483E SPOKANE WA
— 509-352 not yet reported which blocks → ONVOY, LLC - WA 483E SPOKANE WA
— 509-353 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE WA
— 509-354 not yet reported which blocks → QWEST CORPORATION 9638 SPOKANE 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.