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 608
FRONTIER NORTH INC. - WI 53
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
2001-05-11 608-319 1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 DODGEVILLE WI
2001-05-11 608-340 1XXX2XXX3XXX4XXX5XXX6XXX8XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 BRIGGSVL WI
2001-05-11 608-350 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER NORTH INC. - WI 0886 MAUSTON WI
2001-05-11 608-360 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 LOGANVILLE WI
2001-05-11 608-383 1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 RICHLD CTR WI
— 608-253 0XXX which blocks → FRONTIER NORTH INC. - WI 0886 WISCONDLLS WI
— 608-254 0XXX9XXX · 2 holders which blocks → FRONTIER NORTH INC. - WI 0886 WISCONDLLS WI
— 608-296 0XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 WESTFIELD WI
— 608-297 0XXX1XXX3XXX4XXX5XXX6XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 MONTELLO WI
— 608-339 1XXX which blocks → FRONTIER NORTH INC. - WI 0886 ADAMS WI
— 608-423 0XXX2XXX5XXX6XXX8XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 CAMBRIDGE WI
— 608-424 0XXX2XXX4XXX5XXX7XXX8XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 BELLEVILLE WI
— 608-429 0XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 PARDEEVL WI
— 608-455 0XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 BROOKLYN WI
— 608-493 0XXX1XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 MERRIMAC WI
— 608-524 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 REEDSBURG WI
— 608-544 0XXX1XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 WITWEN WI
— 608-546 0XXX1XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 PLAIN WI
— 608-549 0XXX1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 BLOOM CITY WI
— 608-564 0XXX4XXX5XXX6XXX8XXX9XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 MONROE CTR WI
— 608-583 0XXX1XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 LONE ROCK WI
— 608-585 0XXX1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 ITHACA WI
— 608-588 0XXX1XXX4XXX5XXX6XXX8XXX · 5 holders which blocks → FRONTIER NORTH INC. - WI 0886 SPG GREEN WI
— 608-592 0XXX8XXX9XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 LODI WI
— 608-623 0XXX1XXX4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 COBB WI
— 608-643 9XXX which blocks → FRONTIER NORTH INC. - WI 0886 SAUK CITY WI
— 608-644 4XXX5XXX6XXX7XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 SAUK CITY WI
— 608-647 0XXX which blocks → FRONTIER NORTH INC. - WI 0886 RICHLD CTR WI
— 608-655 0XXX2XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER NORTH INC. - WI 0886 MARSHALL WI
— 608-666 4XXX5XXX6XXX7XXX8XXX9XXX · 6 holders which blocks → FRONTIER NORTH INC. - WI 0886 LYNDON STA WI
— 608-676 0XXX1XXX3XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER NORTH INC. - WI 0886 CLINTON WI
— 608-727 4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 LOGANVILLE WI
— 608-742 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 PORTAGE WI
— 608-745 2XXX7XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 PORTAGE WI
— 608-753 3XXX5XXX7XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 ARENA WI
— 608-764 0XXX3XXX4XXX6XXX9XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 DEERFIELD WI
— 608-825 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 SUNPRAIRIE WI
— 608-834 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 SUNPRAIRIE WI
— 608-835 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 OREGON WI
— 608-837 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 SUNPRAIRIE WI
— 608-838 1XXX which blocks → FRONTIER NORTH INC. - WI 0886 MCFARLAND WI
— 608-839 0XXX2XXX6XXX7XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 COTTAGEGRV WI
— 608-847 0XXX8XXX · 2 holders which blocks → FRONTIER NORTH INC. - WI 0886 MAUSTON WI
— 608-879 0XXX1XXX4XXX5XXX6XXX8XXX · 3 holders which blocks → FRONTIER NORTH INC. - WI 0886 ORFORDVL WI
— 608-884 0XXX5XXX · 2 holders which blocks → FRONTIER NORTH INC. - WI 0886 EDGERTON WI
— 608-897 0XXX1XXX5XXX6XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 BRODHEAD WI
— 608-924 0XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 RIDGEWAY WI
— 608-935 not yet reported which blocks → FRONTIER NORTH INC. - WI 0886 DODGEVILLE WI
— 608-937 1XXX2XXX3XXX6XXX8XXX9XXX · 4 holders which blocks → FRONTIER NORTH INC. - WI 0886 DODGEVILLE WI
— 608-967 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER NORTH INC. - WI 0886 HOLLANDALE WI

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.