NumberResearch Membership · Data 09/21/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/21/2026

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
— 410-571 3XXX4XXX5XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-572 1XXX4XXX7XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 SALISBURY MD
— 410-573 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-574 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ESSEX MD
— 410-575 0XXX1XXX2XXX3XXX4XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 FORK MD
— 410-576 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-578 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-579 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 ELKRIDGE MD
— 410-580 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 PIKESVILLE MD
— 410-581 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 PIKESVILLE MD
— 410-582 1XXX2XXX3XXX6XXX7XXX8XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 GLENBURNIE MD
— 410-583 3XXX which blocks → VERIZON MARYLAND, INC. 9212 TOWSON MD
— 410-584 3XXX5XXX which blocks → VERIZON MARYLAND, INC. 9212 COCKEYSVL MD
— 410-585 4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-586 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 PRINCEFRCK MD
— 410-588 6XXX7XXX9XXX which blocks → VERIZON MARYLAND, INC. 9212 BEL AIR MD
— 410-590 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 GLENBURNIE MD
— 410-592 1XXX4XXX which blocks → VERIZON MARYLAND, INC. 9212 FORK MD
— 410-593 0XXX1XXX3XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 FORK MD
— 410-594 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WOODLAWN MD
— 410-597 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WOODLAWN MD
— 410-601 3XXX which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-602 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 PIKESVILLE MD
— 410-604 4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 STEVENSVL MD
— 410-605 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-606 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 WATERLO236 MD
— 410-609 3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 BRYNPKLNCM MD
— 410-612 3XXX which blocks → VERIZON MARYLAND, INC. 9212 EDGEWOOD MD
— 410-613 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-614 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-617 0XXX8XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-620 8XXX which blocks → VERIZON MARYLAND, INC. 9212 ELKTON MD
— 410-621 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → VERIZON MARYLAND, INC. 9212 PRINCEANNE MD
— 410-623 0XXX1XXX3XXX4XXX5XXX6XXX7XXX9XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 MARION MD
— 410-624 2XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-625 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-626 none assigned yet which blocks → VERIZON MARYLAND, INC. 9212 ANNAPOLIS MD
— 410-628 9XXX which blocks → VERIZON MARYLAND, INC. 9212 COCKEYSVL MD
— 410-629 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → VERIZON MARYLAND, INC. 9212 BERLIN MD
— 410-631 3XXX which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-632 6XXX7XXX8XXX · 3 holders which blocks → VERIZON MARYLAND, INC. 9212 SNOW HILL MD
— 410-633 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-634 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → VERIZON MARYLAND, INC. 9212 RIDGELY MD
— 410-635 0XXX1XXX4XXX5XXX7XXX9XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 NEWWINDSOR MD
— 410-636 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BRYNPKLNCM MD
— 410-637 9XXX which blocks → VERIZON MARYLAND, INC. 9212 BALTIMORE MD
— 410-638 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BEL AIR MD
— 410-639 0XXX3XXX4XXX5XXX6XXX8XXX · 5 holders which blocks → VERIZON MARYLAND, INC. 9212 ROCK HALL MD
— 410-641 not yet reported which blocks → VERIZON MARYLAND, INC. 9212 BERLIN MD
— 410-642 4XXX5XXX7XXX · 2 holders which blocks → VERIZON MARYLAND, INC. 9212 PERRYVILLE MD

Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/21/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.