GoPhone prepaid $45 and $60 unlimited plans will rollover to the next month when the plan renews. For example, if a customer on the $60 plan, which includes 4 GB of data, only uses 3 GB in the current month, the unused 1 GB will rollover so the user has 5 GB available in the following month.
The change to rollover data begins May 15. New customers who start service on or after the 15th will get rollover data. Existing customers will begin accumulating rollover data the next time their plan renews after May 15.
While rollover data is nice it's not quite as good deal as it sounds. That's because plan data is used before rollover data and rollover data expires after 30 days. So if a user on the $60 plan has 5 GB high speed data available (4 GB plan data and 1 GB rollover) and they olny use 4 GB they don't get to rollover the unused 1 GB. Still, expiring rollover is better than no rollover at all.
GoPhone's $45 and $60 plans both include unlimited domestic voice minutes, unlimited domestic and international texts, unlimited domestic MMS and WiFi hotspot capability. The $60 plan also includes unlimited calls to Mexico. The $45 plan comes with 1.5 GB of high speed data, the $60 plan includes 4 GB. Both plans have unlimited data throttled to 128 Kbps after the high speed data is used up.
For more about GoPhone see Prepaid Operator Profile: AT&T GoPhone.
Source: AT&T Consumer Blog