1. Look Up the Model Online

Search your phone’s model (e.g., “Samsung Galaxy S21 USB Ethernet support”) and check the official specs or tech forums (like XDA Developers, Reddit, or the manufacturer’s site).

2. Check for OTG (On-The-Go) Support

Most USB-C Ethernet adapters require USB OTG capability.

• Android:

  • Go to Settings > About Phone > USB configuration

    Key Phrases That Mean It Does Support USB-C Ethernet:
    

    "USB OTG (On-The-Go) supported"

    "Ethernet over USB-C supported"

    "Supports USB-C to Ethernet adapter"

    "Wired Ethernet connectivity supported"

    "USB host mode: Yes"

    "Supports USB peripherals via USB-C"

  • ❌ If You See These, It May Not Work:
    

     

    "OTG not supported"

    "Only supports charging/data transfer"

    "Limited USB-C functionality"

    "No USB host support"

    “USB 2.0 only” (in some cases)

  • Or download a free app like USB OTG Checker from the Play Store.

• iPhone:

  • Only iPhone 15 and newer (with USB-C ports) may support Ethernet with Apple-compatible adapters. Check Apple’s support docs.

3. Try It (If You Have the Adapter)

If you already have a USB-C to Ethernet adapter:

• Plug it in.

• Turn off Wi-Fi and mobile data.

• If Ethernet is supported, your phone should connect automatically.

  • On Android: You’ll see a “wired network” or “Ethernet” notification.

  • On iPhone 15+: Ethernet works only with certain adapters—check under Settings > Ethernet if it appears.