Prefix 408-306 — Sunnyvale, CA
The 408-306 prefix belongs to area code 408 and is anchored to the Sunnyvale rate center (CA). In NANP terms, the prefix — or NXX — determines the rate center a number is billed against.
Sunnyvale is part of the San Jose-Sunnyvale-Santa Clara, CA Metropolitan Statistical Area. For routing purposes it sits in LATA 722. Numbers here keep Pacific time.
NANPA's central-office code records list NEW CINGULAR WIRELESS PCS, LLC (OCN 6010) as the code holder, assigned June 25, 2001. Because 408-306 participates in thousands-block pooling, individual 1,000-number blocks may belong to other carriers than the code holder.
Caller ID showing 408-306 is not proof the call came from Sunnyvale: spoofing and porting both detach numbers from their origin. To verify a caller, hang up and dial the organization's published number, and report suspicious calls to the FTC.
Neighboring prefixes
| Prefix | Rate center | Code holder |
|---|---|---|
| 408-303 | Saratoga | T-MOBILE USA, INC. |
| 408-304 | Saratoga | T-MOBILE USA, INC. |
| 408-305 | San Jose:west Da | SPOK, INC. |
| 408-307 | San Jose:west Da | NEW CINGULAR WIRELESS PCS, LLC |
| 408-308 | San Jose:west Da | SPOK, INC. |
| 408-309 | San Jose:west Da | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA |
FAQ
Where is 408-306 located?
The prefix is assigned to the Sunnyvale rate center in CA, area code 408. It is part of the San Jose-Sunnyvale-Santa Clara, CA Metropolitan Statistical Area.
Which company owns 408-306 numbers?
NEW CINGULAR WIRELESS PCS, LLC holds the code, but the prefix is pooled — individual thousands-blocks can be assigned to other carriers, and numbers may be ported to any provider.
Is a call from 408-306 safe to answer?
The prefix itself says nothing about the caller. Legitimate Sunnyvale businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.