You may have various reasons to want to know if a cell phone has been disconnected. Perhaps you are switching phones or carriers, and you want to make sure that you are not getting billed for two phones. Maybe you have just discovered an old phone that you forgot about and now would like to donate or recycle it. In any case, it is relatively easy to check to see whether the phone you are holding has been disconnected.
Charge the phone completely. You will have a difficult time checking to see if it is disconnected if it has no power.
Video of the Day
Turn the phone on and look at its number. Write that number down. Different models of phone have different ways to access that phone's own number, but most of them are fairly straightforward.
Try to dial a number that you know works, such as a landline or another cell phone in your house. If you are successfully able to dial it, you know that the cell phone has not been disconnected.
Call the cell phone service provider and ask whether service has been disconnected for the cell phone number that you wrote down in step 2. In some rare cases, a phone might not work, but an account may still be active with the cell phone provider. You want to make sure that you are not being billed erroneously.