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

MCHENRY prefixes in area code 815

NANPA records 18 assigned NXX blocks to rate center MCHENRY in area code 815, 2.3% 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. 9 holders hold those blocks, the largest being ILLINOIS BELL TEL CO (5), LEVEL 3 COMMUNICATIONS, LLC - IL (4), MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL (2). The earliest assignment on record here is 2002-02-27 and the most recent 2010-08-04. 11 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 701, 779 – overlay codes cover the same geography, so a rate center is served by all of them.

18 assigned blocks – 2.3% of 815
9 holders of record
11 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
815-271 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL – yes yes
815-307 Lumen LEVEL 3 COMMUNICATIONS, LLC - IL – yes yes
815-322 Lumen LEVEL 3 COMMUNICATIONS, LLC - IL – yes yes
815-331 Lumen LEVEL 3 COMMUNICATIONS, LLC - IL – yes yes
815-344 AT&T ILLINOIS BELL TEL CO – no yes
815-349 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL – yes yes
815-363 AT&T ILLINOIS BELL TEL CO – no yes
815-385 AT&T ILLINOIS BELL TEL CO – no yes
815-388 T-Mobile METROPCS, INC. – yes yes
815-403 T-Mobile METROPCS, INC. – yes yes
815-430 FIRST COMMUNICATIONS, LLC – no yes
815-528 AT&T TELEPORT COMMUNICATIONS AMERICA, LLC - IL – yes yes
815-578 AT&T ILLINOIS BELL TEL CO – no yes
815-669 Lumen LEVEL 3 COMMUNICATIONS, LLC - IL – yes yes
815-679 RCN TELECOM SERVICES OF ILLINIOS, INC. - IL – yes yes
815-759 AT&T ILLINOIS BELL TEL CO – no yes
815-900 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL 2010-08-04 yes yes
815-903 American Messaging AMERICAN MESSAGING SERVICES, LLC 2002-02-27 no 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 5 27.8%
LEVEL 3 COMMUNICATIONS, LLC - IL Lumen 4 22.2%
MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL Verizon 2 11.1%
METROPCS, INC. T-Mobile 2 11.1%
FIRST COMMUNICATIONS, LLC – 1 5.6%
TELEPORT COMMUNICATIONS AMERICA, LLC - IL AT&T 1 5.6%
RCN TELECOM SERVICES OF ILLINIOS, INC. - IL – 1 5.6%
NEW CINGULAR WIRELESS PCS, LLC - IL AT&T 1 5.6%
AMERICAN MESSAGING SERVICES, LLC American Messaging 1 5.6%

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 MCHENRY in area code 815?

18 blocks: 271, 307, 322, 331, 344, 349, 363, 385, 388, 403, 430, 528 and 6 more, all listed in the table above.

Which carriers have numbers in MCHENRY?

ILLINOIS BELL TEL CO (5 blocks), LEVEL 3 COMMUNICATIONS, LLC - IL (4 blocks), MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL (2 blocks), METROPCS, INC. (2 blocks), FIRST COMMUNICATIONS, LLC (1 block), TELEPORT COMMUNICATIONS AMERICA, LLC - IL (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is MCHENRY 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