Existing customers will have to consciously opt-in with T-Mobile for this to take effect today. New customers don't have to worry about it.
Last week, T-Mobile announced that the company will add free calling and data to Canada and Mexico for every T-Mobile customer. Of course, they added free international data roaming a while back, which kinda makes it a no-brainer if you travel a lot. (Check out our data tests with it if you haven't already.)
Per the press release:
Beginning July 15th, calls to, from and between the U.S., Mexico & Canada—whether mobile or landline— are included in our latest plans at no extra charge. And, when you’re in Mexico & Canada, you’ll use 4G LTE data straight from your Simple Choice 4G LTE data plan.... As always, you get all the other Un-carrier benefits like Music Freedom and Wi-Fi calling and texting. You’ll be even able to tap into your Data Stash in Mexico & Canada starting later this year.
Everyone’s eligible, including Simple Choice postpaid and prepaid customers. Starting next Wednesday, every new Simple Choice customer will automatically get Mexico & Canada included in their plan at no extra charge. Current Simple Choice customers can simply opt-in online, by phone, or in-store by switching to our latest plans for free. Business customers can also add coverage and calling across North America to their Simple Choice plan at no extra cost for the first 10 lines and only $1 a month for each line beyond that.