NumberResearch Membership · Data 09/25/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/25/2026

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 317
INDIANA BELL TEL CO INC 297
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
— 317-388 5XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-390 4XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-392 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 SHELBYVL IN
— 317-398 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 SHELBYVL IN
— 317-415 3XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-421 6XXX7XXX9XXX · 3 holders which blocks → INDIANA BELL TEL CO INC 9325 SHELBYVL IN
— 317-423 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-428 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-433 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-444 0XXX1XXX9XXX · 2 holders which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-453 0XXX1XXX5XXX6XXX7XXX9XXX · 2 holders which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-462 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 GREENFIELD IN
— 317-464 0XXX3XXX7XXX9XXX · 2 holders which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-465 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-466 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-467 5XXX which blocks → INDIANA BELL TEL CO INC 9325 GREENFIELD IN
— 317-468 2XXX3XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → INDIANA BELL TEL CO INC 9325 GREENFIELD IN
— 317-469 1XXX3XXX6XXX8XXX9XXX · 3 holders which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-470 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-471 7XXX9XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-475 8XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-479 6XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-481 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-484 7XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-486 3XXX9XXX · 2 holders which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-487 9XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-488 0XXX1XXX7XXX8XXX9XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-521 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 FISHERS IN
— 317-541 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-542 2XXX3XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-543 7XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-544 0XXX7XXX8XXX9XXX · 3 holders which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-545 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-546 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-547 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-549 5XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-562 0XXX which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-566 4XXX which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-568 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 INDIANAPLS IN
— 317-569 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-570 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 FISHERS IN
— 317-571 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-573 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-574 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-575 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN
— 317-576 2XXX3XXX4XXX · 2 holders which blocks → INDIANA BELL TEL CO INC 9325 FISHERS IN
— 317-577 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 FISHERS IN
— 317-578 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 FISHERS IN
— 317-579 5XXX which blocks → INDIANA BELL TEL CO INC 9325 FISHERS IN
— 317-580 not yet reported which blocks → INDIANA BELL TEL CO INC 9325 CARMEL IN

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/25/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.