If you don't answer the calls, then no.
Keep in mind, though if you have the phone on and are still receiving calls, it is not just calls which would initiate a 24 hour Travel Pass window. Data usage would do the same thing. If ANY app on your device were to access data while your phone was on and you just weren't answering your calls, the Travel Pass charge would post.
Things which would initiate the 24 hour Travel Pass window would be your phone checking if emails were available for you to view. Texts arriving on your device over the cellular network. ANY other apps which show a notification on your device such as Facebook, Instagram, Snapchat, weather apps, shopping apps, mapping software, etc...
Simply because you are not answering your device does not mean the 24 hour charge would not start. IF you have your phone out of airplane mode where you can still receive calls, it is EXTREMELY likely your device is using the network for other activities, too, not just to hear your phone ringing letting you know there is a call.
Yes, because your device is still connected to the international network. To avoid service charges, please enable Airplane mode. You can learn more here: https://www.verizonwireless.com/support/travelpass-faqs/ . BrittanyC_VZW
We're glad that this information is useful, jalh1. The device will always try to find a cellular network first, so Airplane Mode will stop it from connecting to any wireless network. That way, you are 100% sure that any usage is from your Wi-Fi connection.
Thanks for helping with the question related to the Travel Pass Feature, mama23dogs. Let me help with the question as well as asked. The Travel Pass feature allows access to be able to use your phone when in a Travel Pass country. The Travel Pass feature itself is charged depending on where you are using the service. Which country are you visiting so we can confirm the charge? Here's a link for more details that goes over the charge involved and more helpful details https://www.verizonwireless.com/support/travelpass-faqs/ . Does this help?