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

SANJOAQUIN prefixes in area code 559

NANPA records 7 assigned NXX blocks to rate center SANJOAQUIN in area code 559, 0.9% 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. 5 holders hold those blocks, the largest being FRONTIER CALIFORNIA INC. (3), COMCAST PHONE OF CALIFORNIA, LLC (1), METROPCS, INC. (1). 7 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots.

7 assigned blocks – 0.9% of 559
5 holders of record
7 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
559-210 Comcast COMCAST PHONE OF CALIFORNIA, LLC – yes yes
559-364 T-Mobile METROPCS, INC. – yes yes
559-525 Peerless PEERLESS NETWORK OF CALIFORNIA, LLC - CA – yes yes
559-630 AT&T NEW CINGULAR WIRELESS PCS, LLC – yes yes
559-693 Frontier FRONTIER CALIFORNIA INC. – yes yes
559-698 Frontier FRONTIER CALIFORNIA INC. – yes yes
559-829 Frontier FRONTIER CALIFORNIA INC. – 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 42.9%
COMCAST PHONE OF CALIFORNIA, LLC Comcast 1 14.3%
METROPCS, INC. T-Mobile 1 14.3%
PEERLESS NETWORK OF CALIFORNIA, LLC - CA Peerless 1 14.3%
NEW CINGULAR WIRELESS PCS, LLC AT&T 1 14.3%

Frequently asked

Which prefixes belong to SANJOAQUIN in area code 559?

7 blocks: 210, 364, 525, 630, 693, 698, 829. The table above gives the holder of each.

Which carriers have numbers in SANJOAQUIN?

FRONTIER CALIFORNIA INC. (3 blocks), COMCAST PHONE OF CALIFORNIA, LLC (1 block), METROPCS, INC. (1 block), PEERLESS NETWORK OF CALIFORNIA, LLC - CA (1 block), NEW CINGULAR WIRELESS PCS, 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 SANJOAQUIN 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 559

All 785 prefixes in 559