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

GRANDLEDGE prefixes in area code 517

NANPA records 8 assigned NXX blocks to rate center GRANDLEDGE in area code 517, 1.3% of the 616 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. 6 holders hold those blocks, the largest being FRONTIER NORTH, INC. - MI (3), OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC (1), TELEPORT COMMUNICATIONS AMERICA, LLC - MI (1). The earliest assignment on record here is 2001-11-15 and the most recent 2020-10-20. 7 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots.

8 assigned blocks – 1.3% of 517
6 holders of record
7 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
517-261 T-Mobile OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2020-10-20 yes yes
517-412 AT&T TELEPORT COMMUNICATIONS AMERICA, LLC - MI 2010-05-26 yes yes
517-622 Frontier FRONTIER NORTH, INC. - MI – yes yes
517-626 Frontier FRONTIER NORTH, INC. - MI – yes yes
517-627 Frontier FRONTIER NORTH, INC. - MI – no yes
517-666 Onvoy ONVOY, LLCV - MI 2017-11-21 yes yes
517-731 Lumen LEVEL 3 COMMUNICATIONS, LLC - MI 2009-11-16 yes yes
517-925 ACD TELECOM, INC. - MI 2001-11-15 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. - MI Frontier 3 37.5%
OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC T-Mobile 1 12.5%
TELEPORT COMMUNICATIONS AMERICA, LLC - MI AT&T 1 12.5%
ONVOY, LLCV - MI Onvoy 1 12.5%
LEVEL 3 COMMUNICATIONS, LLC - MI Lumen 1 12.5%
ACD TELECOM, INC. - MI – 1 12.5%

Frequently asked

Which prefixes belong to GRANDLEDGE in area code 517?

8 blocks: 261, 412, 622, 626, 627, 666, 731, 925. The table above gives the holder of each.

Which carriers have numbers in GRANDLEDGE?

FRONTIER NORTH, INC. - MI (3 blocks), OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC (1 block), TELEPORT COMMUNICATIONS AMERICA, LLC - MI (1 block), ONVOY, LLCV - MI (1 block), LEVEL 3 COMMUNICATIONS, LLC - MI (1 block), ACD TELECOM, INC. - MI (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is GRANDLEDGE 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 517

All 616 prefixes in 517