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

GREENFIELD prefixes in area code 831

NANPA records 7 assigned NXX blocks to rate center GREENFIELD in area code 831, 1.7% of the 406 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 ONVOY, LLC - CA (2), BANDWIDTH.COM CLEC, LLC - CA (2), ONVOY SPECTRUM, LLC (1). The earliest assignment on record here is 2019-05-03 and the most recent 2024-03-21. 7 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 217, 317, 413, 417 – overlay codes cover the same geography, so a rate center is served by all of them.

7 assigned blocks – 1.7% of 831
5 holders of record
7 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
831-231 Charter ONVOY SPECTRUM, LLC 2019-05-03 yes yes
831-286 Onvoy ONVOY, LLC - CA 2024-03-21 yes yes
831-304 Peerless PEERLESS NETWORK OF CALIFORNIA, LLC - CA – yes yes
831-388 Onvoy ONVOY, LLC - CA 2022-09-08 yes yes
831-613 Bandwidth BANDWIDTH.COM CLEC, LLC - CA – yes yes
831-674 AT&T PACIFIC BELL – yes yes
831-856 Bandwidth BANDWIDTH.COM CLEC, LLC - CA – 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
ONVOY, LLC - CA Onvoy 2 28.6%
BANDWIDTH.COM CLEC, LLC - CA Bandwidth 2 28.6%
ONVOY SPECTRUM, LLC Charter 1 14.3%
PEERLESS NETWORK OF CALIFORNIA, LLC - CA Peerless 1 14.3%
PACIFIC BELL AT&T 1 14.3%

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 GREENFIELD in area code 831?

7 blocks: 231, 286, 304, 388, 613, 674, 856. The table above gives the holder of each.

Which carriers have numbers in GREENFIELD?

ONVOY, LLC - CA (2 blocks), BANDWIDTH.COM CLEC, LLC - CA (2 blocks), ONVOY SPECTRUM, LLC (1 block), PEERLESS NETWORK OF CALIFORNIA, LLC - CA (1 block), PACIFIC BELL (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is GREENFIELD 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 831

All 406 prefixes in 831