It's great that you are planning ahead for cell phone use in South Korea, Ciris31. We're here to help in every way possible. While the iPhone7 will allow you to use a SIM card from a foreign country while outside the US, we're unable to say for certain which providers would or would not be able to provide service. Have you considered using our global add-on options? More information here: www.vzw.com/tripplanner.
Should you decide you wish to suspend your Verizon service during your trip, you can use this link to do that: http://spr.ly/658189GDc
We hope you have a safe and wonderful trip. Let us know if you have any questions.
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