How do you activate your T-Mobile prepaid cell phone?

Prepaid phone owners may activate their new devices on the T-Mobile website or by calling 844-730-5912. Charge the battery fully, and insert the SIM card into the phone before activating it.

The SIM card number, phone serial number and activation code from the phone's instruction booklet are required for activation. Customers who have lost their activation code must call T-Mobile from the new phone to request another code. Enter the required phone and personal information, and choose a service plan. Enter a credit card or checking account number to fund the new T-Mobile account, and finalize the activation process. To start using the phone, add credit.