It's really important before you start this process to make sure you have the following:
1. A T-Mobile signal so you can receive a text
2. Your old phone and SIM
3. Your new SIM
If you got a replacement SIM because your old one was lost, stolen, faulty or damaged, it will already be active. You only need to use this service if you requested a new SIM because your old one wouldn’t fit in your new phone.
When you've entered your mobile number and hit 'Submit' we'll text you a 4 digit PIN
Don't worry about your contacts
Once your new SIM is activated and your old SIM is disconnected from the network,
you can still use the old one to transfer your contacts.