NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026

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 314
SOUTHWESTERN BELL 255
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
— 314-345 0XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-351 8XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-352 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-353 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-355 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-361 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-362 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-364 not yet reported which blocks → SOUTHWESTERN BELL 9533 SAPPINGTON MO
— 314-367 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-371 5XXX6XXX7XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-381 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-382 8XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-383 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-385 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-388 8XXX which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-389 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-415 0XXX1XXX2XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-416 not yet reported which blocks → SOUTHWESTERN BELL 9533 MEHLVILLE MO
— 314-418 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-421 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-423 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-425 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-426 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-427 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-428 9XXX which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-429 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-432 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-434 not yet reported which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-436 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-438 2XXX3XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-439 1XXX6XXX8XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-444 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-445 1XXX2XXX4XXX5XXX7XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-453 2XXX3XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-454 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-457 3XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-465 0XXX1XXX2XXX3XXX5XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-466 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-469 not yet reported which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-480 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-481 9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-487 not yet reported which blocks → SOUTHWESTERN BELL 9533 MEHLVILLE MO
— 314-489 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-493 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-505 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-506 not yet reported which blocks → SOUTHWESTERN BELL 9533 LADUE MO
— 314-512 not yet reported which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO
— 314-514 4XXX5XXX which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-515 not yet reported which blocks → SOUTHWESTERN BELL 9533 CREVECOEUR MO
— 314-516 3XXX which blocks → SOUTHWESTERN BELL 9533 ST LOUIS MO

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.