Oct 15, 2011
Mobile phone carriers in the past have been a bit dicey about allowing customers to upgrade their phones and keep their existing plans, so a lot of iPhone owners who got in early with AT&T and Verizon and purchased unlimited data plans are understandably concerned about their possibilities for upgrading to the iPhone 4S and keeping their unlimited data plans. According to our research, the answer is “yes’ for both AT&T and Verizon customers; you can get the iPhone 4S without changing your plan.
AT&T: According to 9 to 5 Mac, the trick is to remove the “Unlimited Data for iPhone” plan during the upgrade process. When you do this, the “Unlimited Data for iPhone 4S” plan becomes available. Add this plan and complete the upgrade.
Verizon: On June 23, 2011, Verizon Wireless confirmed via its official Twitter account that customers can keep their unlimited data plans when upgrading to another smartphone. The text appears to be white-on-white, so you may need to highlight it to read it.
So, upgrade without fear; if you are one of the lucky AT&T or Verizon iPhone owners who got in early and grabbed an unlimited data plan, you can get the iPhone 4S without stepping down to a limited plan.