No you do not have to have a data or texting plan for this phone, It is just considered a Quick Messaging Phone by AT&T, doesn't require any special plan to have it. One can be added if desired, but it is not required.... been working for AT&T for 3 years now.
The LG Xpression and LG Xpression 2 do not require a text messaging or data plan. They are quick messaging phones. Quick messaging phones do not require either of those plans. They can be added on if you want.