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 410
VERIZON MARYLAND, INC. 510
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
2007-08-16 410-417 0–9 XXXall 10 · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 EDGEWOOD MD
2005-06-28 410-470 0–9 XXXwhole prefix which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
2005-05-10 410-577 0–9 XXXwhole prefix which blocks → VERIZON MARYLAND, INC. 9212 PIKESVILLE MD
2005-03-11 410-858 0–9 XXXall 10 · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
2001-08-21 410-941 0XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 JARRETTSVL MD
— 410-201 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-203 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ELLICOTTCY MD
— 410-204 0XXX1XXX2XXX3XXX4XXX5XXX8XXX9XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 ARBUTUS MD
— 410-208 5XXX7XXX8XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 BERLIN MD
— 410-209 0XXX7XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-213 3XXX4XXX5XXX6XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 OCEAN CITY MD
— 410-216 0XXX1XXX2XXX3XXX4XXX5XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-217 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-219 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 SALISBURY MD
— 410-221 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 CAMBRIDGE MD
— 410-222 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 SEVERN MD
— 410-223 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-224 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-225 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-226 1XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → VERIZON MARYLAND, INC. 9212 OXFORD MD
— 410-228 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 CAMBRIDGE MD
— 410-229 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 COCKEYSVL MD
— 410-230 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-233 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-234 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-235 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-237 0XXX1XXX4XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-238 9XXX which blocks → VERIZON MARYLAND, INC. 9212 ESSEX MD
— 410-239 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 REISTERSTN MD
— 410-242 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ARBUTUS MD
— 410-243 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-244 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-247 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ARBUTUS MD
— 410-248 5XXX7XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 PARKVILLE MD
— 410-249 none assigned yet which blocks → VERIZON MARYLAND, INC. 9212 TOWSON MD
— 410-250 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 OCEAN CITY MD
— 410-252 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 TOWSON MD
— 410-254 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-255 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ARGRGBSNIS MD
— 410-256 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 PARKVILLE MD
— 410-257 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 NORTHBEACH MD
— 410-260 0XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 SEVERNA PK MD
— 410-261 0XXX4XXX6XXX9XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-263 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-264 1XXX2XXX6XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 WATERLO236 MD
— 410-265 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WOODLAWN MD
— 410-266 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-267 3XXX4XXX which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-268 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-269 3XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 SEVERNA PK MD

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.