How to find ICCID?
The Sim Card number(ICCID) can be found on the back of the Card containing the SIM.

How To Replace A Physical SIM Card
Only proceed with the steps below after your new SIM card has been activated on the T-Mobile network.
1. Turn off your device.
2. Eject the SIM card tray on your device.
3. Remove the existing SIM card. Place your new T-Mobile SIM card into your device by aligning it to the shape of the SIM card tray and laying it flat.

4. Put the SIM tray back into your device.
Before You Activate A New Device
Follow the tips below to ensure a smooth activation process. We recommend doing the activation on a computer or device different from the one you’re activating.
- Don't remove your old SIM card until the activation is complete. Replacing a physical SIM card with a new one? Please hold off on swapping them until you see a confirmation screen at the end of the activation process.
- Back up your important device content. Make sure to back up your photos, contacts, calendar, and other data before you start the activation process. Need help? Check out our Back up and Content Transfer guide.
- Connect to Wi-Fi. If you’re using a mobile device, we recommend that you connect to Wi-Fi as you may temporarily lose network service during the activation.
- Have your companion devices nearby. If you have Apple Watch, Galaxy Watch, or other companion devices paired with your old device, please make sure they’re within reach.