AT&T Business Device Activation Guide • Updated July 29, 2026
Activate an AT&T business phone, tablet, hotspot, or watch
Get what you need, activate the line, and complete the eSIM download if prompted. Follow these steps in order.
1. What you need before you start
- The wireless number being activated: use the existing number for an upgrade or port, or the assigned number for a new line.
- The billing ZIP or shipping ZIP associated with the account or order.
- The new device powered on and ready for setup.
- A Wi-Fi network and password if the new device uses eSIM.
2. Activate the AT&T line
- If the new device uses eSIM, connect it to Wi-Fi and keep it connected throughout activation. If it uses a physical SIM, make sure the AT&T SIM is installed.
- Start the activation online at att.com/activations/activatewireless or call 866-895-1099.
- If activating online, enter the wireless number and billing or shipping ZIP, then follow the AT&T prompts.
- For an eSIM device: while AT&T is activating the line, wait for the Download eSIM notification. It can take a few minutes to appear. Tap the notification and follow the prompts to download the AT&T eSIM and the wireless number being activated. Do not transfer an eSIM from another phone and do not use a QR code.
- When activation and the eSIM download are finished, restart the device. If it uses a physical SIM, restart it after AT&T confirms the activation.
- Test calling, texting, and cellular data. For a tablet or hotspot, test its cellular-data connection.
3. If the number is being transferred from another carrier
- Do not cancel service with the old provider. The old service must remain active while the number is being transferred.
- Complete the AT&T activation steps above, including the eSIM download if prompted.
- Turn both phones off: the old provider’s phone and the new AT&T phone.
- Turn on only the new AT&T phone. Leave the old provider’s phone turned off.
- Test calling, texting, and cellular data on the AT&T phone.
4. Apple Watch activation and NumberSync
Activating the Apple Watch line is only the first step. If the watch will use the same number as an iPhone, it must also be linked through AT&T NumberSync.
Follow the complete instructions: How to Add or Remove AT&T NumberSync for Apple Watch.
5. Before erasing or trading in the old phone
- Transfer your photos, contacts, apps, and other information. See the Smartphone Content Transfer Guide.
- Place and receive a test call.
- Send and receive a test text message.
- Turn off Wi-Fi and confirm cellular data works.
Only erase, reset, or trade in the old phone after the information is transferred and every test above works on the new phone.
Need AT&T Business upgrades, new lines, or devices?
Contact Curtis Matthews before ordering for current business promotions, device availability, and multi-line ordering.
If the activation does not work
The activation page says “Not Activated”
- Confirm the wireless number: existing number for an upgrade or port, or assigned number for a new line.
- Try the account billing ZIP. If it is not accepted, try the shipping ZIP used for the order.
- Submit the activation again.
The eSIM notification does not appear
- Confirm the device is still connected to Wi-Fi.
- Allow a few minutes after the activation confirmation.
- Do not use the transfer or QR-code options.
- If the notification still does not arrive, call 866-895-1099.
A physical-SIM device has no service
- Power the device off.
- Confirm the AT&T SIM is installed correctly.
- Power the device back on and test it again.
- If it still has no service, call 866-895-1099.
