Project Fi can tell you in advance if your destination is supported by its service
Google's hybrid MVNO Project Fi has added 37 new countries to its international coverage list. With the new additions, Project Fi now supplies talk, text and data to 170 countries around the world. Pricing remains the same for text and data. Unlimited texting is offered in all countries on the list and
data remains priced at $10/GB until Bill Protection kicks in, limiting your monthly payment at $80 ($60 for data + $20 for talk/text). Phone calls outside of the U.S. are billed at 20 cents per minute and are not included in Bill Protection.
Project Fi will even send out a notification to let you know if you are covered by the MVNO when you are going out of the country. Based on your correspondence in Gmail, Project Fi knows where you're going and will tell you whether it can provide service there.
Now might be a good time for you to take a look at Project Fi. In fact, the MVNO is running a deal that gives away a free month of individual service (worth $80) to a subscriber who purchases a new phone from Project Fi. The choices are limited to the four currently available Pixel phones, the
Moto X4(Android One model),
Nexus 6,
Nexus 6P and the
Nexus 5X.
These countries now are covered by the Project Fi MVNO" 
source:
Google
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