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

WESTFIELD prefixes in area code 317

NANPA records 7 assigned NXX blocks to rate center WESTFIELD in area code 317, 0.9% 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. 3 holders hold those blocks, the largest being FRONTIER NORTH, INC.. - IN (4), BANDWIDTH.COM CLEC, LLC - IN (2), LEVEL 3 TELECOM OF INDIANA, LP - IN (1). The earliest assignment on record here is 2001-05-22 and the most recent 2018-08-27. 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 codes 217, 281, 336, 346 – overlay codes cover the same geography, so a rate center is served by all of them.

7 assigned blocks – 0.9% of 317
3 holders of record
5 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
317-399 Lumen LEVEL 3 TELECOM OF INDIANA, LP - IN 2001-05-22 yes yes
317-763 Bandwidth BANDWIDTH.COM CLEC, LLC - IN 2014-06-17 yes yes
317-785 Bandwidth BANDWIDTH.COM CLEC, LLC - IN 2018-08-27 yes yes
317-804 Frontier FRONTIER NORTH, INC.. - IN – yes yes
317-867 Frontier FRONTIER NORTH, INC.. - IN – no yes
317-877 Frontier FRONTIER NORTH, INC.. - IN – no yes
317-896 Frontier FRONTIER NORTH, INC.. - IN – 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
FRONTIER NORTH, INC.. - IN Frontier 4 57.1%
BANDWIDTH.COM CLEC, LLC - IN Bandwidth 2 28.6%
LEVEL 3 TELECOM OF INDIANA, LP - IN Lumen 1 14.3%

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 WESTFIELD in area code 317?

7 blocks: 399, 763, 785, 804, 867, 877, 896. The table above gives the holder of each.

Which carriers have numbers in WESTFIELD?

FRONTIER NORTH, INC.. - IN (4 blocks), BANDWIDTH.COM CLEC, LLC - IN (2 blocks), LEVEL 3 TELECOM OF INDIANA, LP - IN (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is WESTFIELD 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 317

All 786 prefixes in 317