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

LAKE MILLS prefixes in area code 920

NANPA records 4 assigned NXX blocks to rate center LAKE MILLS in area code 920, 0.5% 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. 3 holders hold those blocks, the largest being T-MOBILE USA, INC. (2), FRONTIER NORTH INC. - WI (1), CHARTER IP ENABLED SERVICES, LLC (1). The earliest assignment on record here is 2006-01-20 and the most recent 2006-01-20. 4 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 274, 641 – overlay codes cover the same geography, so a rate center is served by all of them.

4 assigned blocks – 0.5% of 920
3 holders of record
4 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
920-222 T-Mobile T-MOBILE USA, INC. – yes yes
920-297 T-Mobile T-MOBILE USA, INC. – yes yes
920-648 Frontier FRONTIER NORTH INC. - WI – yes yes
920-945 Charter CHARTER IP ENABLED SERVICES, LLC 2006-01-20 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
T-MOBILE USA, INC. T-Mobile 2 50%
FRONTIER NORTH INC. - WI Frontier 1 25%
CHARTER IP ENABLED SERVICES, LLC Charter 1 25%

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 LAKE MILLS in area code 920?

4 blocks: 222, 297, 648, 945. The table above gives the holder of each.

Which carriers have numbers in LAKE MILLS?

T-MOBILE USA, INC. (2 blocks), FRONTIER NORTH INC. - WI (1 block), CHARTER IP ENABLED SERVICES, LLC (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is LAKE MILLS 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 920

All 785 prefixes in 920