NumberingData
Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

WARREN prefixes in area code 409

NANPA records 3 assigned NXX blocks to rate center WARREN in area code 409, 0.7% of the 434 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. 3 holders hold those blocks, the largest being ONVOY, LLC - TX (1), COMMIO, LLC (1), SOUTHWESTERN BELL (1). The earliest assignment on record here is 2021-07-06 and the most recent 2023-12-22. 3 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 codes 207, 208, 218, 234 – overlay codes cover the same geography, so a rate center is served by all of them.

3 assigned blocks – 0.7% of 409
3 holders of record
3 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
409-278 Onvoy ONVOY, LLC - TX 2021-07-06 yes yes
409-323 COMMIO, LLC 2023-12-22 yes yes
409-547 AT&T SOUTHWESTERN BELL – 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

HolderBrandBlocksShare here
ONVOY, LLC - TX Onvoy 1 33.3%
COMMIO, LLC – 1 33.3%
SOUTHWESTERN BELL AT&T 1 33.3%

Same rate center in other codes

Overlay codes cover the same geography, so one rate center is served by all of them.

Frequently asked

Which prefixes belong to WARREN in area code 409?

3 blocks: 278, 323, 547. The table above gives the holder of each.

Which carriers have numbers in WARREN?

ONVOY, LLC - TX (1 block), COMMIO, LLC (1 block), SOUTHWESTERN BELL (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is WARREN 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.

Other rate centers in 409

All 434 prefixes in 409