How much do you have to pay for Blackberry data plan at AT&T? Now you can have data plan for Blackberry as cheap as just $15 a month (limit to 200mb data). This is good for those who occasionally check emails and surf the Internet. Heavy data users can opt for $25 that gives you 2GB a month. If you want more like unlimited data, Sorry, AT&T doesn’t offer all-you-can-eat data plan anymore. If you already have an unlimited data plan with AT&T, we strong recommend you not to change to the 2 tired plans mentioned above. Once you change it you can never go back to the old plan. So, the right way to do it is simply ask for a phone upgrade and keep the same Blackberry data plan. That way you don’t need to watch data usage as you stream videos and audio over AT&T’s wireless network.