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

ALTO prefixes in area code 575

NANPA records 4 assigned NXX blocks to rate center ALTO in area code 575, 0.8% of the 521 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 BANDWIDTH.COM CLEC, LLC - NM (2), VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1), MESCALERO APACHE TELECOM, INC. - NM (1). The earliest assignment on record here is 2005-12-12 and the most recent 2015-09-01. 2 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 616, 936 – overlay codes cover the same geography, so a rate center is served by all of them.

4 assigned blocks – 0.8% of 575
3 holders of record
2 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
575-228 Bandwidth BANDWIDTH.COM CLEC, LLC - NM 2014-10-13 yes yes
575-336 Windstream VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW – no yes
575-498 MESCALERO APACHE TELECOM, INC. - NM 2005-12-12 no yes
575-729 Bandwidth BANDWIDTH.COM CLEC, LLC - NM 2015-09-01 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
BANDWIDTH.COM CLEC, LLC - NM Bandwidth 2 50%
VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW Windstream 1 25%
MESCALERO APACHE TELECOM, INC. - NM – 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 ALTO in area code 575?

4 blocks: 228, 336, 498, 729. The table above gives the holder of each.

Which carriers have numbers in ALTO?

BANDWIDTH.COM CLEC, LLC - NM (2 blocks), VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW (1 block), MESCALERO APACHE TELECOM, INC. - NM (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is ALTO 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 575

All 521 prefixes in 575