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

ROUND LAKE prefixes in area code 847

NANPA records 5 assigned NXX blocks to rate center ROUND LAKE in area code 847, 0.6% 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. 2 holders hold those blocks, the largest being ILLINOIS BELL TEL CO (3), LEVEL 3 COMMUNICATIONS, LLC - IL (2). The earliest assignment on record here is 2005-02-10 and the most recent 2005-02-10. 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 224, 507, 518, 838 – overlay codes cover the same geography, so a rate center is served by all of them.

5 assigned blocks – 0.6% of 847
2 holders of record
3 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
847-201 Lumen LEVEL 3 COMMUNICATIONS, LLC - IL – yes yes
847-270 AT&T ILLINOIS BELL TEL CO – yes yes
847-546 AT&T ILLINOIS BELL TEL CO – no yes
847-740 AT&T ILLINOIS BELL TEL CO – no yes
847-886 Lumen LEVEL 3 COMMUNICATIONS, LLC - IL 2005-02-10 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 3 60%
LEVEL 3 COMMUNICATIONS, LLC - IL Lumen 2 40%

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 ROUND LAKE in area code 847?

5 blocks: 201, 270, 546, 740, 886. The table above gives the holder of each.

Which carriers have numbers in ROUND LAKE?

ILLINOIS BELL TEL CO (3 blocks), LEVEL 3 COMMUNICATIONS, LLC - IL (2 blocks). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is ROUND LAKE 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 847

All 786 prefixes in 847