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
Clear Download CSV ↓
Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 585-241 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-242 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-243 8XXX which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 GENESEO NY
— 585-244 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-245 0XXX1XXX2XXX3XXX4XXX · 2 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 GENESEO NY
— 585-246 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-247 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-248 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-249 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-251 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-253 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-254 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-255 0XXX which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-256 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-258 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-259 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 ROCHESTER NY
— 585-260 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ROCHESTER NY
— 585-261 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 ROCHESTER NY
— 585-262 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-263 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-264 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 EROCHESTER NY
— 585-265 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 WEBSTER NY
— 585-266 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-268 0XXX1XXX2XXX3XXX4XXX6XXX8XXX · 5 holders which blocks → VERIZON NEW YORK, INC. 9104 BELMONT NY
— 585-271 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-272 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-273 none assigned yet which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-274 none assigned yet which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-275 not yet reported which blocks → LEVEL 3 TELECOM OF NEW YORK, LP - NY 8473 ROCHESTER NY
— 585-276 0–9 XXXwhole prefix which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-277 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-279 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-280 0–9 XXXall 10 · 7 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 WEBSTER NY
— 585-281 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - DC 4036 ROCHESTER NY
— 585-283 0–9 XXXall 10 · 6 holders which blocks → TWC IP ENABLED SERVICES, LLC 793K ALBION NY
— 585-288 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-289 1XXX5XXX7XXX · 2 holders which blocks → WINDSTREAM NEW YORK, INC. - RED JACKET 0113 SHORTSVL NY
— 585-291 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-292 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-293 5XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 CHURCHVL NY
— 585-294 0XXX1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 6 holders which blocks → TWC IP ENABLED SERVICES, LLC 793K CALEDONIA NY
— 585-295 3XXX which blocks → PAETEC ITEL, LLC 829J ROCHESTER NY
— 585-300 0–9 XXXall 10 · 5 holders which blocks → OMNIPOINT COMMUNICATIONS, INC. - NY 6622 BATAVIA NY
— 585-303 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS, INC. - NY 6622 ROCHESTER NY
— 585-305 none assigned yet which blocks → OMNIPOINT COMMUNICATIONS, INC. - NY 6622 ROCHESTER NY
— 585-306 not yet reported which blocks → FRONTIER TELEPHONE OF ROCHESTER, INC. 0121 ROCHESTER NY
— 585-307 3XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 OLEAN NY
— 585-311 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX NY
— 585-313 6XXX which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 ROCHESTER NY
— 585-314 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - NY 6959 ROCHESTER 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.