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 217
ILLINOIS BELL TEL CO 129
FRONTIER NORTH, INC. - IL 114
NEW CINGULAR WIRELESS PCS, LLC - IL 72
LEVEL 3 COMMUNICATIONS, LLC - IL 59
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 51
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
— 217-915 5XXX6XXX7XXX9XXX · 3 holders which blocks → ONVOY, LLC 224C AUBURN IL
— 217-917 2XXX3XXX5XXX9XXX · 3 holders which blocks → TELNYX LLC 073H DECATUR IL
— 217-923 1XXX2XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER COMMUNICATIONS OF THE CAROLINAS, INC - IL 1000 GREENUP IL
— 217-924 not yet reported which blocks → MONTROSE MUTUAL TEL. CO. 1058 MONTROSE IL
— 217-925 not yet reported which blocks → MONTROSE MUTUAL TEL. CO. 1058 DIETERICH IL
— 217-927 2XXX3XXX7XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 PATTERSON IL
— 217-930 0XXX2XXX · 2 holders which blocks → LEVEL 3 COMMUNICATIONS, LLC - IL 6115 CARLINVL IL
— 217-932 3XXX8XXX · 2 holders which blocks → FRONTIER COMMUNICATIONS OF THE CAROLINAS, INC - IL 1000 CASEY IL
— 217-934 0XXX4XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 CLINTON IL
— 217-935 not yet reported which blocks → FRONTIER NORTH, INC. - IL 1015 CLINTON IL
— 217-936 not yet reported which blocks → ADAMS TEL. COOP. 0976 MENDON IL
— 217-937 5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → FRONTIER NORTH, INC. - IL 1015 CLINTON IL
— 217-938 not yet reported which blocks → ADAMS TEL. COOP. 0976 LORAINE IL
— 217-941 1XXX7XXX8XXX · 3 holders which blocks → ONVOY SPECTRUM, LLC 624H KENNEY IL
— 217-942 7XXX which blocks → FRONTIER NORTH, INC. - IL 1015 CARROLLTON IL
— 217-944 1XXX4XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 KENNEY IL
— 217-945 4XXX5XXX7XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 HILLVIEW IL
— 217-946 not yet reported which blocks → GRANDVIEW MUTUAL TEL. CO. 1021 GRANDVIEW IL
— 217-947 1XXX4XXX6XXX · 3 holders which blocks → FRONTIER NORTH, INC. - IL 1015 ELKHART IL
— 217-948 1XXX7XXX8XXX · 2 holders which blocks → FRONTIER COMMUNICATIONS OF THE CAROLINAS, INC - IL 1000 KANSAS IL
— 217-949 0XXX9XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 WAYNESVL IL
— 217-950 not yet reported which blocks → IL
— 217-952 0–9 XXXall 10 · 7 holders which blocks → TELNYX LLC 073H ATHENS IL
— 217-953 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → ONVOY, LLC 224C SPRINGFLD IL
— 217-955 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 6 holders which blocks → MCC TELEPHONY LLC 593K GREENVIEW IL
— 217-956 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 MATTOON IL
— 217-957 not yet reported which blocks → AMERICAN MESSAGING SERVICES, LLC 9748 MATTOON IL
— 217-958 not yet reported which blocks → MULTIPLE OCN LISTING MULT XXXXXXXXXX IL
— 217-959 not yet reported which blocks → MULTIPLE OCN LISTING MULT IL
— 217-962 2XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 2 holders which blocks → T-MOBILE USA, INC. 6529 MATTOON IL
— 217-963 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → ILLINOIS BELL TEL CO 9329 HARRISTOWN IL
— 217-964 not yet reported which blocks → ADAMS TEL. COOP. 0976 URSA IL
— 217-965 0XXX2XXX6XXX7XXX8XXX · 4 holders which blocks → FRONTIER NORTH, INC. - IL 1015 VIRDEN IL
— 217-967 1XXX2XXX6XXX7XXX9XXX · 3 holders which blocks → FRONTIER COMMUNICATIONS OF THE CAROLINAS, INC - IL 1000 WESTFIELD IL
— 217-968 not yet reported which blocks → CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 1183 GREENVIEW IL
— 217-970 0–9 XXXall 10 · 6 holders which blocks → COMCAST IP PHONE, LLC 318J SPRINGFLD IL
— 217-971 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 SPRINGFLD IL
— 217-972 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 DECATUR IL
— 217-975 not yet reported which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 MATTOON IL
— 217-976 not yet reported which blocks → IL
— 217-979 0XXX4XXX5XXX6XXX8XXX · 2 holders which blocks → NEW CINGULAR WIRELESS PCS, LLC - IL 6534 CHAMPAURBN IL
— 217-980 0XXX1XXX2XXX3XXX7XXX8XXX9XXX · 6 holders which blocks → MCC TELEPHONY LLC 593K NAUVOO IL
— 217-983 3XXX4XXX7XXX · 2 holders which blocks → FRONTIER NORTH, INC. - IL 1015 ELDRED IL
— 217-985 not yet reported which blocks → ADAMS TEL. COOP. 0976 LIMA IL
— 217-987 1XXX2XXX3XXX4XXX7XXX8XXX9XXX · 5 holders which blocks → FRONTIER COMMUNICATIONS OF THE CAROLINAS, INC - IL 1000 POTOMAC IL
— 217-991 0XXX1XXX2XXX3XXX8XXX9XXX · 6 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 6333 CHAMPAURBN IL
— 217-993 0–9 XXXall 10 · 6 holders which blocks → EXIANT COMMUNICATIONS LLC 114J SPRINGFLD IL
— 217-994 0–9 XXXall 10 · 4 holders which blocks → CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 6333 EFFINGHAM IL
— 217-997 3XXX4XXX · 2 holders which blocks → FRONTIER COMMUNICATIONS-MIDLAND, INC. 1055 ARENZVILLE IL
— 217-999 3XXX8XXX · 2 holders which blocks → CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 1183 MOUNTOLIVE 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.