When you purchase a T-Mobile myTouch smartphone, the device is locked to T-Mobile service using a password called a SIM lock. As long as the lock is active, the myTouch will not work with another carrier's network, so you have to unlock it to switch the myTouch to another carrier. SIM is short for Subscriber Identity Module, and comes in the form of a plastic card about the size of a postage stamp -- it carries the network information and phone number, along with contacts and text messages.
Obtain the SIM lock code. Purchase the code from an unlocking service, or contact T-Mobile customer care. T-Mobile will give you the code as long as your account meets certain criteria: for postpaid accounts, your account must be active at least 40 days; for prepaid accounts, your account must be active at least 60 days, with a minimum balance of $10 or a deposit within the last 30 days.
2
Turn off the myTouch and flip the phone over.
3
Press the top left corner and slide the back of the phone toward the bottom edge.
4
Remove the battery by lifting from the top edge. Set the battery and battery cover aside.
5
Remove the T-Mobile SIM card and insert another carrier's SIM card. The contacts should face into the phone, with the beveled corner on the top left.
6
Reinstall the battery and battery cover, and turn the phone back on. The phone displays a message asking for a "SIM network unlock PIN."
7
Type the code using the on-screen keyboard and touch the "Unlock" button.
Tips & Warnings
Contact T-Mobile customer care by dialing 611 from your myTouch, or calling 800-937-8997 from another line.
