Verizon has confirmed (here, here and here) they will unlock the SIM on the iPhone 4S, allowing for use of foreign SIM cards while traveling abroad, or for use of foreign SIM cards roaming on GSM networks in the United States (this will not allow for AT&T or T-Mobile SIM card use.) This is different than the jailbreak unlocking method; SIM unlocking through Verizon is permanent, free, and will not affect your warranty in any way. 1. Meet the following requirements: * Must be a Verizon Wireless customer. * The iPhone 4S being unlocked must be active on a Verizon Wireless line of service. * The line of service must be active at least 60 days. * The line of service must be in good standing for the past 60 days. * Only one SIM Unlock per line every 10 months. If you don't meet one or more of the above requirements, call anyway. You may still get lucky. 2. Insert a foreign SIM into the SIM card slot on the side of your phone (only needed to confirm the unlock is successful.) 3. Call 1-800-711-8300 (Verizon Global Support), select option 2, and ask the representative for a SIM unlock. Occassionally a representative may not know exactly what you are referring to; make sure you are not transferred to a different department. You are in the right place. Explain that they should have a walkthrough on how to do this, and that it allows for the use of local, non-Verizon SIM cards while traveling abroad. 4. Get confirmation from the rep that the unlock has been applied to your account, then check your phone to make sure it recognizes your SIM and can connect (if successful it will roam on AT&T, assuming you are calling from the USA.) You will NOT see an unlock confirmation in iTunes as that is for a factory-applied unlock only. 5. Enjoy your new unlocked iPhone 4S!