MONMOUTH prefixes in area code 309
NANPA records 8 assigned NXX blocks to rate center MONMOUTH in area code 309, 1.0% of the 786 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 7 holders hold those blocks, the largest being CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL (2), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL (1), MTC COMMUNICATIONS, INC. - IL (1). The earliest assignment on record here is 2003-01-24 and the most recent 2026-03-24. 5 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots. The same rate center name also appears in area code 207 – overlay codes cover the same geography, so a rate center is served by all of them.
Prefixes assigned here
| Prefix | Holder of record | Assigned | Pooled | In service |
|---|---|---|---|---|
| 309-457 | Frontier CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL | – | no | yes |
| 309-536 | Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 2003-01-24 | yes | yes |
| 309-715 | MTC COMMUNICATIONS, INC. - IL | 2015-01-21 | no | yes |
| 309-734 | Frontier CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL | – | no | yes |
| 309-760 | Lumen LEVEL 3 COMMUNICATIONS, LLC - IL | 2005-08-16 | yes | yes |
| 309-816 | IP HORIZON LLC | 2020-09-18 | yes | yes |
| 309-971 | NUSO, LLC | 2025-04-04 | yes | yes |
| 309-990 | EXIANT COMMUNICATIONS LLC | 2026-03-24 | yes | yes |
The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.
Who holds the blocks
| Holder | Brand | Blocks | Share here |
|---|---|---|---|
| CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL | Frontier | 2 | 25% |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | Verizon | 1 | 12.5% |
| MTC COMMUNICATIONS, INC. - IL | – | 1 | 12.5% |
| LEVEL 3 COMMUNICATIONS, LLC - IL | Lumen | 1 | 12.5% |
| IP HORIZON LLC | – | 1 | 12.5% |
| NUSO, LLC | – | 1 | 12.5% |
| EXIANT COMMUNICATIONS LLC | – | 1 | 12.5% |
Frequently asked
Which prefixes belong to MONMOUTH in area code 309?
8 blocks: 457, 536, 715, 734, 760, 816, 971, 990. The table above gives the holder of each.
Which carriers have numbers in MONMOUTH?
CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL (2 blocks), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL (1 block), MTC COMMUNICATIONS, INC. - IL (1 block), LEVEL 3 COMMUNICATIONS, LLC - IL (1 block), IP HORIZON LLC (1 block), NUSO, LLC (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.
Is MONMOUTH a city?
It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.