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

CASS CITY prefixes in area code 989

NANPA records 5 assigned NXX blocks to rate center CASS CITY in area code 989, 0.7% of the 723 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. 5 holders hold those blocks, the largest being INTERACTIVE SERVICES NETWORK, INC. (1), OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC (1), ONVOY, LLCV - MI (1). The earliest assignment on record here is 2001-06-27 and the most recent 2021-12-09. 3 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots.

5 assigned blocks – 0.7% of 989
5 holders of record
3 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
989-367 INTERACTIVE SERVICES NETWORK, INC. 2002-01-17 no yes
989-431 T-Mobile OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 2021-12-09 yes yes
989-559 Onvoy ONVOY, LLCV - MI 2014-10-06 yes yes
989-872 Frontier FRONTIER NORTH, INC. - MI – no yes
989-912 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL 2001-06-27 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
INTERACTIVE SERVICES NETWORK, INC. – 1 20%
OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC T-Mobile 1 20%
ONVOY, LLCV - MI Onvoy 1 20%
FRONTIER NORTH, INC. - MI Frontier 1 20%
NEW CINGULAR WIRELESS PCS, LLC - IL AT&T 1 20%

Frequently asked

Which prefixes belong to CASS CITY in area code 989?

5 blocks: 367, 431, 559, 872, 912. The table above gives the holder of each.

Which carriers have numbers in CASS CITY?

INTERACTIVE SERVICES NETWORK, INC. (1 block), OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC (1 block), ONVOY, LLCV - MI (1 block), FRONTIER NORTH, INC. - MI (1 block), NEW CINGULAR WIRELESS PCS, 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 CASS CITY 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 989

All 723 prefixes in 989