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

DOS PALOS prefixes in area code 209

NANPA records 6 assigned NXX blocks to rate center DOS PALOS in area code 209, 0.8% of the 784 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 FRONTIER CALIFORNIA INC. (3), ONVOY, LLC - CA (2), COMMIO, LLC (1). The earliest assignment on record here is 2022-05-09 and the most recent 2022-05-09. 6 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 code 350 – overlay codes cover the same geography, so a rate center is served by all of them.

6 assigned blocks – 0.8% of 209
3 holders of record
6 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
209-364 Frontier FRONTIER CALIFORNIA INC. – yes yes
209-387 Frontier FRONTIER CALIFORNIA INC. – yes yes
209-392 Frontier FRONTIER CALIFORNIA INC. – yes yes
209-435 Onvoy ONVOY, LLC - CA – yes yes
209-935 Onvoy ONVOY, LLC - CA 2022-05-09 yes yes
209-973 COMMIO, LLC – 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
FRONTIER CALIFORNIA INC. Frontier 3 50%
ONVOY, LLC - CA Onvoy 2 33.3%
COMMIO, LLC – 1 16.7%

Frequently asked

Which prefixes belong to DOS PALOS in area code 209?

6 blocks: 364, 387, 392, 435, 935, 973. The table above gives the holder of each.

Which carriers have numbers in DOS PALOS?

FRONTIER CALIFORNIA INC. (3 blocks), ONVOY, LLC - CA (2 blocks), COMMIO, 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 DOS PALOS 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 209

All 784 prefixes in 209