Coverage · ZIP 94546
Internet Providers in Castro Valley, CA (94546)
There are 11 internet providers available in Castro Valley, CA (ZIP 94546), including Sonic, AT&T Fiber, Xfinity. Compare each provider below by technology, maximum advertised speed, and area coverage, then call (833) 261-0564 for help choosing a plan. Coverage data is sourced from the FCC National Broadband Map.
Internet providers in Castro Valley, CA (ZIP 94546)
There are 11 residential internet providers available in Castro Valley, CA (ZIP 94546), including Sonic, AT&T Fiber, Xfinity. The table below lists each provider with its technology type, maximum advertised speeds, and area coverage, sourced from the FCC National Broadband Map.
| Provider | Technology | Max download | Max upload | Area coverage |
|---|---|---|---|---|
| Sonic | Fiber | 10 Gbps | 10 Gbps | 59% |
| AT&T Fiber | Fiber | 5 Gbps | 5 Gbps | 59% |
| Xfinity | Cable | 2 Gbps | 250 Mbps | 69% |
| Verizon 5G Home | 5G Home Internet | 300 Mbps | 30 Mbps | 60% |
| Unwired | 5G Home Internet | 300 Mbps | 25 Mbps | 33% |
| T-Mobile Home Internet | 5G Home Internet | 100 Mbps | 20 Mbps | 69% |
| AT&T Internet Air | 5G Home Internet | 100 Mbps | 20 Mbps | 52% |
| Starlink | Satellite | 280 Mbps | 30 Mbps | 100% |
| Viasat | Satellite | 150 Mbps | 3 Mbps | 100% |
| HughesNet | Satellite | 100 Mbps | 5 Mbps | 100% |
| AT&T Internet | DSL | 100 Mbps | 20 Mbps | 53% |
Internet in Castro Valley, CA — common questions
How many internet providers are available in Castro Valley, CA?
There are 11 internet providers available in Castro Valley, CA (ZIP 94546), including Sonic, AT&T Fiber, Xfinity. Availability varies by exact address.
What is the fastest internet available in 94546?
Sonic offers the highest advertised download speed in Castro Valley, CA at up to 10 Gbps. Actual speeds depend on the plan and your address.
How do I check internet availability at my address in Castro Valley, CA?
Enter your ZIP code on Ziatan to see every provider serving your block, then call (833) 261-0564 for help comparing plans and pricing — free, with no signup required.