408 Area Code — San Jose, California
Reviewed by Jordan Lee, Digital Safety Researcher — Last updated January 2026
About the 408 Area Code
Area code 408 covers San Jose, California—one of North America's most forward-leaning telecommunications markets, where VoIP, hosted PBX, and app-based calling have largely displaced traditional wireline infrastructure. All national carriers—AT&T Mobility, Verizon Wireless, and T-Mobile USA—compete for subscribers alongside cloud communication platforms. San Jose, Sunnyvale, and Santa Clara anchor this high-density corridor, which operates on Pacific time.
Key Information
- Region: San Jose
- State / Province: California
- Timezone: Pacific
- Major Cities: San Jose, Sunnyvale, Santa Clara
Area Code Overview
Area code 408 is one of California's original 1947 area codes, serving San Jose, Santa Clara, Sunnyvale, Campbell, Los Gatos, Milpitas, and Cupertino — the geographic heart of Silicon Valley. Overlay code 669 was added in 2012 to meet demand. San Jose is the largest city in the San Francisco Bay Area by population and hosts major headquarters including Apple (Cupertino), Cisco, eBay, Adobe, and Western Digital. The workforce skews heavily toward foreign-born tech professionals on H-1B and other work visas — a demographic that attracts a specific class of immigration-related fraud.
Scam Patterns in 408
H-1B Visa and Immigration Status Fraud
Silicon Valley's large immigrant tech workforce is targeted by texts impersonating USCIS, the Department of Labor, or immigration attorneys — warning of H-1B status violations, expired work authorization, or deportation risk unless fees are paid immediately. The BBB has noted that immigration scams disproportionately concentrate in Bay Area zip codes due to the high density of visa-status workers.
Semiconductor and Trade Secret Phishing
408 hosts Intel, Nvidia, Marvell, and Qualcomm facilities. Scammers send texts impersonating corporate IT security, warning of a "breach" on a work device and directing recipients to surrender credentials or install remote access software. The FBI has identified Silicon Valley as a hotspot for state-sponsored phishing targeting semiconductor intellectual property.
Fake Technical Recruiting
Texts offer positions at recognizable Silicon Valley companies, directing candidates to unofficial portals that harvest personal data or request payment for background checks and "software licensing fees" before a remote orientation that never occurs.
VoIP and Spoofing Risk Assessment
Risk Level: HIGH
Silicon Valley's tech ecosystem means a large percentage of legitimate 408 business lines are already VoIP — corporate PBX systems and cloud phones are standard. This normalization makes spoofed 408 numbers harder to identify by line type alone. USCIS impersonators specifically use VoIP 408 numbers to appear locally credible to Bay Area visa workers.
What To Do If You Receive a Text From a 408 Number
Step 1: Know that USCIS never contacts by text. Immigration authorities communicate by mail. Any text claiming immigration status issues is a scam. See our guide on how to identify spoofed text messages.
Step 2: Look up the number. Run it through Who Sent That Text Message to check for prior reports and carrier data before responding or calling back.
Step 3: Treat unsolicited job offers as unverified. If a text offers a role at a Silicon Valley company, find the posting on that company's official careers page — no legitimate employer processes a relocation offer via cold text.
Step 4: Report. Forward to 7726 (SPAM). Report immigration scams to the USCIS tip line at 1-800-375-5283. File with the FTC at reportfraud.ftc.gov.
Frequently Asked Questions
What area code is 408?
Area code 408 serves San Jose and Silicon Valley, including Santa Clara, Sunnyvale, Cupertino, Campbell, and Milpitas in Santa Clara County. It is one of California's original 1947 area codes, sharing territory with overlay 669.
Is area code 408 used for scams?
408 is a legitimate Silicon Valley area code. Because 408 is associated with tech companies and a large immigrant workforce, it is used in H-1B visa impersonation scams, fake tech recruiting, and corporate credential phishing. An unknown 408 text claiming immigration, job, or IT security urgency deserves immediate skepticism.
Why does Silicon Valley's visa worker population attract disproportionate immigration scam texts?
H-1B and other visa workers face a specific vulnerability: any credible threat to their immigration status means potential job loss and forced departure. Scammers exploit this fear asymmetry — a visa worker's urgency to resolve a claimed status problem makes them more likely to pay fees or share documentation without first verifying independently. The Bay Area's concentration of visa workers makes it a high-return target.
Related Area Codes
Carriers & Network Type for 408 Numbers
Network mix: Mobile-heavy — most 408 numbers are assigned to mobile lines.
Common Scam Patterns
FCC complaint data for 408 numbers includes:
- Tech support scam
- Robocall/Auto-dialer
- Spoofed caller ID
- Credit card services
If You Got a Text from 408
Who Typically Calls from the 408 Area Code?
Area code 408 covers San Jose, California—one of North America's most forward-leaning telecommunications markets, where VoIP, hosted PBX, and app-based calling have largely displaced traditional wireline infrastructure. All national carriers—AT&T Mobility, Verizon Wireless, and T-Mobile USA—compete for subscribers alongside cloud communication platforms. San Jose, Sunnyvale, and Santa Clara anchor this high-density corridor, which operates on Pacific time. Calls from 408 numbers originate in San Jose, California. Residents, local businesses, schools, medical offices, and government agencies in this region all use 408 numbers. If you received an unexpected call or text from a 408 number, it may be a neighbor, a local service provider, or — in some cases — an unwanted solicitor.
Because 408 is a legitimate, widely used area code, scammers sometimes spoof it to make their calls appear local and trustworthy. This technique — called neighbor spoofing — makes it more likely that recipients will answer. A reverse phone lookup is the fastest way to find out whether a 408 number is genuinely local or spoofed.
Is a 408 Phone Number Spam?
Not all 408 calls are spam, but the area code is not immune to robocall campaigns and phone scams. Common complaints about 408 numbers include warranty extension scams, debt collection harassment, IRS impersonation calls, and unsolicited insurance offers.
If a 408 number called you and didn't leave a voicemail, that's a red flag — legitimate callers typically leave a message. Use Who Sent That Text Message to look up the number instantly and see whether other users have flagged it as spam.
You can also report a suspicious 408 number directly from our lookup results, helping protect others in the community from the same caller.
Look Up a 408 Number Now
Enter any 408 area code phone number below and get instant results — carrier, line type, caller name (where available), and spam reports submitted by real users.
Other Area Codes in California
California has multiple area codes serving different regions. If the number you received isn't from 408, check one of the other California area codes below.
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