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

RIALTO prefixes in area code 909

NANPA records 34 assigned NXX blocks to rate center RIALTO in area code 909, 4.3% of the 786 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. 13 holders hold those blocks, the largest being PACIFIC BELL (8), METROPCS NETWORKS, LLC (5), BANDWIDTH.COM CLEC, LLC - CA (4). The earliest assignment on record here is 2005-12-16 and the most recent 2018-03-15. 28 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 840 – overlay codes cover the same geography, so a rate center is served by all of them.

34 assigned blocks – 4.3% of 909
13 holders of record
28 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
909-233 T-Mobile METROPCS NETWORKS, LLC 2007-03-20 yes yes
909-237 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA – yes yes
909-258 T-Mobile METROPCS NETWORKS, LLC 2008-07-21 yes yes
909-265 T-Mobile METROPCS NETWORKS, LLC 2009-01-31 yes yes
909-271 Onvoy ONVOY, LLC - CA 2009-02-11 yes yes
909-301 Bandwidth BANDWIDTH.COM CLEC, LLC - CA 2011-08-05 yes yes
909-341 Charter TWC IP ENABLED SERVICES, LLC 2012-03-16 yes yes
909-419 Lumen LEVEL 3 TELECOM OF CALIFORNIA, LP - CA – yes yes
909-421 AT&T PACIFIC BELL – no yes
909-440 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA – yes yes
909-442 T-Mobile T-MOBILE USA, INC. 2016-11-02 yes yes
909-543 Lumen LEVEL 3 COMMUNICATIONS, LLC - CA – yes yes
909-546 Verizon MCIMETRO ACCESS TRANSMISSION SERVICES LLC – yes yes
909-562 AT&T PACIFIC BELL – yes yes
909-566 Bandwidth BANDWIDTH.COM CLEC, LLC - CA 2015-04-24 yes yes
909-586 Lumen LEVEL 3 COMMUNICATIONS, LLC - CA – yes yes
909-640 AT&T AT&T ENTERPRISES, LLC 2016-08-05 yes yes
909-644 Lumen LEVEL 3 COMMUNICATIONS, LLC - CA – yes yes
909-666 Bandwidth BANDWIDTH.COM CLEC, LLC - CA – yes yes
909-676 T-Mobile METROPCS NETWORKS, LLC 2014-12-24 yes yes
909-685 AT&T NEW CINGULAR WIRELESS PCS, LLC 2006-07-10 yes yes
909-745 T-Mobile T-MOBILE USA, INC. 2015-09-16 yes yes
909-746 TPx U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS – yes yes
909-787 Onvoy ONVOY, LLC - CA 2016-02-16 yes yes
909-820 AT&T PACIFIC BELL – no yes
909-873 AT&T PACIFIC BELL – no yes
909-874 AT&T PACIFIC BELL – no yes
909-875 AT&T PACIFIC BELL – no yes
909-877 AT&T PACIFIC BELL – no yes
909-879 AT&T PACIFIC BELL – yes yes
909-955 T-Mobile METROPCS NETWORKS, LLC 2018-03-15 yes yes
909-961 T-Mobile T-MOBILE USA, INC. 2005-12-16 yes yes
909-990 Charter TWC IP ENABLED SERVICES, LLC 2013-03-18 yes yes
909-999 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
PACIFIC BELL AT&T 8 23.5%
METROPCS NETWORKS, LLC T-Mobile 5 14.7%
BANDWIDTH.COM CLEC, LLC - CA Bandwidth 4 11.8%
T-MOBILE USA, INC. T-Mobile 3 8.8%
LEVEL 3 COMMUNICATIONS, LLC - CA Lumen 3 8.8%
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA Verizon 2 5.9%
ONVOY, LLC - CA Onvoy 2 5.9%
TWC IP ENABLED SERVICES, LLC Charter 2 5.9%
LEVEL 3 TELECOM OF CALIFORNIA, LP - CA Lumen 1 2.9%
MCIMETRO ACCESS TRANSMISSION SERVICES LLC Verizon 1 2.9%
AT&T ENTERPRISES, LLC AT&T 1 2.9%
NEW CINGULAR WIRELESS PCS, LLC AT&T 1 2.9%
U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS TPx 1 2.9%

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 RIALTO in area code 909?

34 blocks: 233, 237, 258, 265, 271, 301, 341, 419, 421, 440, 442, 543 and 22 more, all listed in the table above.

Which carriers have numbers in RIALTO?

PACIFIC BELL (8 blocks), METROPCS NETWORKS, LLC (5 blocks), BANDWIDTH.COM CLEC, LLC - CA (4 blocks), T-MOBILE USA, INC. (3 blocks), LEVEL 3 COMMUNICATIONS, LLC - CA (3 blocks), CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA (2 blocks). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is RIALTO 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 909

All 786 prefixes in 909