How to Activate Your AT&T Business Phone Service: Step-by-Step Guide

Welcome, new AT&T business customers! Whether you’re setting up a new phone, bringing your own device (BYOD), or porting a number, this guide makes activating your AT&T business service simple and fast.

🔁 Activation Scenarios Overview

  1. Bring Your Own Device (BYOD): Activate instantly with a new AT&T SIM or eSIM.

  2. Port-In: Transfer your number from another carrier using your account details.

  3. Upgrade: Replace your current device with new equipment on your existing AT&T number.

📲 Step-by-Step AT&T Business Phone Activation

  1. Step 1: Connect to Wi-Fi
    Power on your device and connect to a stable Wi-Fi network. (Wi-Fi is required for eSIM downloads.)

    Step 2: Initiate Activation by Phone
    From a different phone, call the AT&T Business Activation Line: 📞 866-895-1099
    Follow the automated prompts to activate your new device.

    Step 3: Manual Activation (If Needed)
    Go to att.com/activate and enter:

    • IMEI (found in device settings or on the box)

    • ICCID (SIM card number, found on the SIM or packaging)

    • Billing ZIP code or account ID

🧾 Activating eSIM Devices

After activation is confirmed:

  • You may see a “Download eSIM” prompt — tap to continue
    OR

  • Go to Settings > Cellular > Add Cellular Plan and follow the instructions

Wi-Fi is required to download the eSIM profile.

🔄 Transferring Content

  • Back up your old phone using iCloud, Google, or AT&T’s content transfer guides.

  • Follow device-specific prompts to transfer your apps, contacts, and data.

✅ Confirm Activation

Make a test call, use mobile data, or check for a 5G/LTE signal to ensure everything is working.

🛠️ Troubleshooting Common Issues

  • Porting Delays: Ensure your old account is active and unlocked. Contact your previous carrier if the port stalls.

  • eSIM Errors: Restart your phone and confirm a strong Wi-Fi signal.

  • No Signal: Re-enter IMEI/ICCID at att.com/activate or call 📞 866-895-1099.

📞 Need Help?

📞 Need Help?