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 303
SPOK, INC. 31
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
— 303-201 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-206 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-207 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-208 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-213 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-230 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-240 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-251 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-266 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-461 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-490 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-540 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-553 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-560 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-599 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-609 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-610 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-612 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-613 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-686 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-687 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-760 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-821 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-826 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-851 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-852 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-855 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-878 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-890 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-891 not yet reported which blocks → SPOK, INC. 6630 DENVER CO
— 303-897 not yet reported which blocks → SPOK, INC. 6630 DENVER CO

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.