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 815
ILLINOIS BELL TEL CO 157
FRONTIER NORTH, INC. - IL 133
LEVEL 3 COMMUNICATIONS, LLC - IL 76
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 50
AERO NORTH COMMUNICATIONS, INC. - IL 43
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
— 815-784 0XXX which blocks → FRONTIER NORTH, INC. - IL 1036 GENOA IL
— 815-785 0XXX1XXX2XXX4XXX5XXX6XXX8XXX9XXX · 8 holders which blocks → RCN TELECOM SERVICES OF ILLINIOS, INC. - IL 8702 WATSEKA IL
— 815-786 0XXX which blocks → FRONTIER NORTH, INC. - IL 1015 SANDWICH IL
— 815-787 not yet reported which blocks → FRONTIER NORTH, INC. - IL 1036 DE KALB IL
— 815-789 0XXX1XXX2XXX5XXX6XXX7XXX8XXX · 6 holders which blocks → FRONTIER NORTH, INC. - IL 1036 ORANGEVL IL
— 815-790 none assigned yet which blocks → T-MOBILE USA, INC. 6529 WOODSTOCK IL
— 815-792 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX9XXX · 7 holders which blocks → ILLINOIS BELL TEL CO 9329 HARDING IL
— 815-794 1XXX4XXX which blocks → MARSEILLES TEL. CO. OF MARSEILLES 1050 MARSEILLES IL
— 815-795 none assigned yet which blocks → MARSEILLES TEL. CO. OF MARSEILLES 1050 MARSEILLES IL
— 815-796 5XXX6XXX · 2 holders which blocks → FRONTIER COMMUNICATIONS-PRAIRIE, INC. 1073 FLANAGAN IL
— 815-798 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F MILLEDGEVL IL
— 815-801 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F FREEPORT IL
— 815-804 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F PECATONICA IL
— 815-805 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F DURAND IL
— 815-806 5XXX6XXX7XXX · 3 holders which blocks → ILLINOIS BELL TEL CO 9329 FRANKFORT IL
— 815-807 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F GERMAN VLY IL
— 815-808 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F WINSLOW IL
— 815-809 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F LENA IL
— 815-810 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F PEARL CITY IL
— 815-811 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IL
— 815-812 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F DAKOTA IL
— 815-813 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F APPLERIVER IL
— 815-816 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F CEDARVILLE IL
— 815-817 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F HANOVER IL
— 815-818 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F WARREN IL
— 815-819 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F ORANGEVL IL
— 815-820 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F ELIZABETH IL
— 815-823 0–9 XXXall 10 · 4 holders which blocks → T-MOBILE USA, INC. 6529 JOLIET IL
— 815-824 0XXX1XXX3XXX4XXX5XXX6XXX7XXX · 6 holders which blocks → FRONTIER NORTH, INC. - IL 1036 SHABBONA IL
— 815-825 0XXX1XXX3XXX4XXX5XXX8XXX · 6 holders which blocks → FRONTIER NORTH, INC. - IL 1036 MALTA IL
— 815-827 0XXX1XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER NORTH, INC. - IL 1036 MAPLE PARK IL
— 815-829 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F CHADWICK IL
— 815-830 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 OGLESBY IL
— 815-831 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F DAVIS IL
— 815-832 not yet reported which blocks → FRONTIER COMMUNICATIONS OF ILLINOIS, INC. 1038 SAUNEMIN IL
— 815-833 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F MCCONNELL IL
— 815-834 3XXX7XXX · 2 holders which blocks → ILLINOIS BELL TEL CO 9329 LOCKPORT IL
— 815-835 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F DIXON IL
— 815-836 1XXX4XXX6XXX9XXX which blocks → ILLINOIS BELL TEL CO 9329 LOCKPORT IL
— 815-837 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F FORRESTON IL
— 815-838 not yet reported which blocks → ILLINOIS BELL TEL CO 9329 LOCKPORT IL
— 815-839 0XXX1XXX2XXX3XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL 7196 KANKAKEE IL
— 815-840 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F STOCKTON IL
— 815-841 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F MT MORRIS IL
— 815-842 7XXX which blocks → FRONTIER NORTH, INC. - IL 1015 PONTIAC IL
— 815-843 not yet reported which blocks → AERO NORTH COMMUNICATIONS, INC. - IL 443F ASHTON IL
— 815-844 0XXX8XXX9XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 PONTIAC IL
— 815-845 0XXX1XXX3XXX4XXX7XXX8XXX · 5 holders which blocks → FRONTIER NORTH, INC. - IL 1036 SCALESMOND IL
— 815-846 not yet reported which blocks → LEVEL 3 COMMUNICATIONS, LLC - IL 6115 JOLIET IL
— 815-848 not yet reported which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 6333 PONTIAC IL

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.