Voicemails found on iPhone that shouldn't be there Recently, a friend of mine who borrowed my old iPhone 5 informed the that he was able to listen to all my old as well as new voicemails (so they were updated on the iPhone 5 as well).

Before I gave him the phone I did the following:


Erase all contents
Log out from my Apple ID
remove all connections / log out from all accounts on the phone (iMessage, ...)
Remove the phone from my Apple ID (via iTunes)
Erase all content &amp; reset the phone


(* during that process, the phone did not have a SIM card inserted.)

Are voicemails connected to my Apple ID? And if not, how could this happen?

(Should I inform my telecommunication provider about this matter?)
Make sure that your friend does not have your SIM card or the voicemail password you set up with your carrier.  If those two things are save your voicemail should be as well.