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

PORTAGE prefixes in area code 608

NANPA records 9 assigned NXX blocks to rate center PORTAGE in area code 608, 1.1% of the 785 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. 7 holders hold those blocks, the largest being UNITED STATES CELLULAR - WI (2), FRONTIER NORTH INC. - WI (2), T-MOBILE USA, INC. (1). The earliest assignment on record here is 2001-02-12 and the most recent 2025-02-28. 8 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 219, 419, 435, 582 – overlay codes cover the same geography, so a rate center is served by all of them.

9 assigned blocks – 1.1% of 608
7 holders of record
8 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
608-566 T-Mobile T-MOBILE USA, INC. 2001-11-02 yes yes
608-617 UNITED STATES CELLULAR - WI 2001-02-12 yes yes
608-683 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WI 2012-10-01 yes yes
608-686 Onvoy ONVOY, LLC - WI 2020-04-13 yes yes
608-697 UNITED STATES CELLULAR - WI – yes yes
608-742 Frontier FRONTIER NORTH INC. - WI – no yes
608-745 Frontier FRONTIER NORTH INC. - WI – yes yes
608-810 Lumen LEVEL 3 COMMUNICATIONS, LLC - WI 2021-11-05 yes yes
608-970 T-Mobile METROPCS, INC. 2025-02-28 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
UNITED STATES CELLULAR - WI – 2 22.2%
FRONTIER NORTH INC. - WI Frontier 2 22.2%
T-MOBILE USA, INC. T-Mobile 1 11.1%
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WI Verizon 1 11.1%
ONVOY, LLC - WI Onvoy 1 11.1%
LEVEL 3 COMMUNICATIONS, LLC - WI Lumen 1 11.1%
METROPCS, INC. T-Mobile 1 11.1%

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 PORTAGE in area code 608?

9 blocks: 566, 617, 683, 686, 697, 742, 745, 810, 970. The table above gives the holder of each.

Which carriers have numbers in PORTAGE?

UNITED STATES CELLULAR - WI (2 blocks), FRONTIER NORTH INC. - WI (2 blocks), T-MOBILE USA, INC. (1 block), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WI (1 block), ONVOY, LLC - WI (1 block), LEVEL 3 COMMUNICATIONS, LLC - WI (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is PORTAGE 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 608

All 785 prefixes in 608