GoPhone prepaid plan will be able to use 4 GB of high speed data at no extra cost while roaming in Mexico and Canada. The $60 plan will also include unlimited talk and text from the US to Mexico and Canada.
Surprisingly AT&T's press release announcing the changes doesn't mention voice and text roaming IN Mexico and Canada, only data. I suspect that's an oversight as including high speed data but not voice and text would be unusual although not impossible.
Update 8/23/15: A GoPhone $60 plan user has confirmed that the description of the plan on the their paygonline.com GoPhone account page says it includes unlimited talk and messaging as well as 4 GB of high speed data while roaming in Mexico and Canada. International use must not exceed 50% of total use per month for more than three consecutive months.
AT&T's latest move follows the trend by US operators to include free international roaming.
- T-Mobile started it by giving postpaid customers unlimited text and 2G data roaming in 120 countries last year.
- On July 15, 2015, T-Mobile gave its prepaid and postpaid Simple Choice Plan customers unlimited free calling and texting to Canada and Mexico plus unlimited voice, text and LTE data roaming in the two countries. On the same date T-Mobile's MetroPCS customers got unlimited Mexican calling, texting and LTE data roaming until 2016 on $40 and higher plans.
- AT&T's Cricket prepaid brand added unlimited calling and texting to Mexico in $50 and higher plans on 2/11/15 and to Canada on 4/20/15. On August 2, Cricket customers got free Mexican voice and text roaming and they are supposed to get free Canadian roaming sometime this month.
- TracFone's Simple Mobile, which is owned by Mexican based multi-nation operator Telcel, added unlimited Mexican talk, text and data roaming for customers on its $60 and higher international plans starting August 4, 2015.
Simple Mobile Shakes Up Plans With New Unlimited Mexico Roaming, Unlimited, Unthrottled Data Plan and More
Cricket To Include Mexico and Canada Roaming With $50 and $60 Plans
Confirmed: MetroPCS Offering Unlimited Mexico Calling and Roaming For Free Until 2016
T-Mobile Adds Free Canada and Mexico Calling and Roaming to Simple Choice Prepaid Plans
Prepaid Operator Profile: AT&T GoPhone