adding an existing iphone to my plan - any reason not to?

[mattkime]

i have an iphone 4 that is under contract until february. my girlfriend has an iphone 3gs that is no longer under contract. it seems that we'd save a fair amount of money by putting her on my account. Any reason not to? (would it limit our upgrade options? etc)

How does it work cost-wise? Its kind of difficult to find this out on att's website.

[macphanatic]

I would look at ATT's add a line. Should be $10 month (sharing cellphone minutes), plus data. Unlimited texting adds $30/month, but you get free mobile to mobile (any carrier).

[cbelt3]

Should work. It's a nice relationship test too. ;-)

[Done]

Well at least you will have a girl friend for two years. Kinda risky unless your pretty sure it's going to last, might get stuck with a large cell phone bill if it doesn't.

If you move to her account you can both get upgraded phones and sell your iPhone 4 for more than you will pay for the upgrade phone. But it should be cheaper with two iPhones on one account, maybe not by a lot but if you both have unlimited texting you can now have family texting and that will save $10.00.

If you do have unlimited texting make sure you get at least 700 minutes of talk time, then you get free mobile to mobile anytime any carrier.