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

SO BELOIT prefixes in area code 815

NANPA records 3 assigned NXX blocks to rate center SO BELOIT in area code 815, 0.4% 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 ILLINOIS BELL TEL CO (1), TDS METROCOM, LLC (1), PAETEC ITEL, LLC (1). The earliest assignment on record here is 2001-02-23 and the most recent 2001-02-23. 1 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 779 – overlay codes cover the same geography, so a rate center is served by all of them.

3 assigned blocks – 0.4% of 815
3 holders of record
1 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
815-389 AT&T ILLINOIS BELL TEL CO – no yes
815-525 TDS TDS METROCOM, LLC – no yes
815-704 Windstream PAETEC ITEL, LLC 2001-02-23 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
ILLINOIS BELL TEL CO AT&T 1 33.3%
TDS METROCOM, LLC TDS 1 33.3%
PAETEC ITEL, LLC Windstream 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 SO BELOIT in area code 815?

3 blocks: 389, 525, 704. The table above gives the holder of each.

Which carriers have numbers in SO BELOIT?

ILLINOIS BELL TEL CO (1 block), TDS METROCOM, LLC (1 block), PAETEC ITEL, 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 SO BELOIT 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 815

All 786 prefixes in 815