Airplane mode on with wifi....no charge for any email messages back and forth

Airplane mode on with wifi and wifi calling enabled...same as above but calls/texts sent to USA AND RECEIVED from USA are not charged.. Obviously emails work to anywhere. Calls to a different country than the USA are charged a nominal rate.

When I was in Aruba a couple of months ago (airplane mode ALWAYS on) I made a test call to our car rental agency to confirm an earlier departure time...maybe a 4-5 minute call. My phone warned me that there would be charges...I was billed right around $2.50 for that call ($1.99 + tax) and zero for the other calls to and from the USA. I could have used the International Plan to make the call but it would have cost $10 for the day. I did not need it for the rest of the day since the wifi worked fine all week

Use whatever you feel comfortable with....