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 585
FRONTIER TELEPHONE OF ROCHESTER, INC. 186
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 69
ONVOY, LLC- NY 56
NEW CINGULAR WIRELESS PCS, LLC - DC 47
VERIZON NEW YORK, INC. 40
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
— 585-383 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-384 1XXX2XXX3XXX4XXX6XXX7XXX8XXX · 6 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 COHOCTON NY
— 585-385 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-387 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-388 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 FAIRPORT NY
— 585-389 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-391 0XXX2XXX3XXX4XXX5XXX8XXX9XXX · 5 holders which blocks → PAETEC ITEL, LLC 829J BROCKPORT NY
— 585-392 not yet reported which blocks → OGDEN TELCO NY DBA FRONTIER OGDEN TELEPHONE CO 0110 HILTON NY
— 585-393 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 CANANDAGUA NY
— 585-394 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 CANANDAGUA NY
— 585-395 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 BROCKPORT NY
— 585-396 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 CANANDAGUA NY
— 585-398 1XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 VICTOR NY
— 585-399 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-411 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX NY
— 585-412 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → TC SYSTEMS, INC. - NY 7140 CANANDAGUA NY
— 585-414 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS, INC. - NY 6622 ROCHESTER NY
— 585-415 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS, INC. - NY 6622 ROCHESTER NY
— 585-416 0–9 XXXall 10 · 4 holders which blocks → ONVOY, LLC- NY 384C WATERPORT NY
— 585-418 4XXX5XXX9XXX · 3 holders which blocks → TWC IP ENABLED SERVICES, LLC 793K E PEMBROKE NY
— 585-419 0XXX1XXX4XXX5XXX8XXX9XXX · 4 holders which blocks → PAETEC ITEL, LLC 829J EROCHESTER NY
— 585-420 6XXX7XXX8XXX which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-421 6XXX7XXX8XXX · 3 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 FAIRPORT NY
— 585-422 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 WEBSTER NY
— 585-423 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-424 0XXX which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-425 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 FAIRPORT NY
— 585-426 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-427 none assigned yet which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-428 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-429 0XXX which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-431 0–9 XXXall 10 · 9 holders which blocks → PAETEC ITEL, LLC 829J BROCKPORT NY
— 585-436 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-437 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → VERIZON NEW YORK, INC. 9104 RUSHFORD NY
— 585-438 0–9 XXXall 10 · 9 holders which blocks → TWC IP ENABLED SERVICES, LLC 793K AVON NY
— 585-442 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-451 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ROCHESTER NY
— 585-452 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-453 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-454 8XXX9XXX · 2 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-455 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 ROCHESTER NY
— 585-457 0XXX1XXX2XXX4XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → VERIZON NEW YORK, INC. 9104 JAVA NY
— 585-458 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-461 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-462 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-463 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-464 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-466 0XXX1XXX2XXX4XXX5XXX6XXX8XXX9XXX · 5 holders which blocks → VERIZON NEW YORK, INC. 9104 ANGELICA NY
— 585-467 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-468 1XXX4XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 NUNDA NY

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.