How to Check If a Cell Phone Is Locked

by Michael Davidson

As cell phones became more advanced, the security features implemented to prevent misuse have also improved. The phone's keypad will lock after a period of inactivity to prevent buttons from being pushed accidentally. This can prevent accidental calls or menu activations. Another type of phone lock is when the phone company programs the phone to only operate with a SIM card issued by them. They do this as a way to ensure that you can't use another service provider, especially when you are in a roaming zone. It is easy to learn if your phone has either type of lock in place.

Data Entry Locks


Examine the screen on the phone and see if it reads "Keyguard" or some other phrase indicating that a screen lock is in effect.


Enter the first few digits of any phone number. If the numbers appear on the screen as you enter them, the phone is not locked.


Access the menu to launch a phone application, such as Internet or text message. If you are able to open the application, the phone is unlocked. If the keypad lock is activated, you should see that message when you try to open the program.

Service Provider Lock


Remove the SIM card from your phone. The SIM card is usually located under the battery. Take off the battery cover and remove the battery, which should expose the SIM card. Remove the SIM card by pulling or sliding it out. Some phones have a release latch for the SIM card that, when pushed, will slide the card out for you.


Insert a SIM card from another cell provider. It must be from a different company than the one you are testing.


Dial a phone number and call someone. If the call is completed and the phone works normally, the phone is not locked. If you get a message saying it can't complete the call or if it asks for a password, the phone is locked.


  • check The SIM card tip only works with GSM phones. GSM (Global System for Mobile Communications) is a type of cell phone formatting used by most phones around the world. It is the international standard. If your phone is formatted as CDMA (Code Division Multiple Access), it is automatically locked to one service provider. Sprint, Nextel, and Verizon typically use CDMA.

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About the Author

Michael Davidson started writing screenplays in 2003 and has had a screenplay professionally produced. He has also studied martial arts since 1990 and has worked as a licensed security specialist. Davidson has written articles for various websites. He is a graduate of Michigan State University and holds a Bachelor of Arts in advertising.

Photo Credits

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