There are voice over ip apps that will allow you to make calls over wifi without roaming charges. I use my Xfinity app when outside the U.S. and call home for free. Vonage also offers a VoIP app and so does google.
That is always the safest route when outside the U.S. While in Canada, phone calls and data will have roaming charges without an international plan. These charges can add up fast. In Canada only, texting is included in your more everything plan with no international texting charges.