Just back from a month in Europe - France and Croatia - on business and pleasure.
Took all the advised precautions with our smart phones:
Turned off Data Roaming
Turned off Location Service
Set Notifications to manual
Turned off Wi-Fi
Activated Airplane Mode
Turned off Cellular Data (which limits all web, email and notifications to Wi-Fi connection only)
De-activated all email addresses
Turned off Call Forwarding and Call Waiting
Our plan was to limit our phone use to absolutely necessary calls only and limit our communications to texting - for which we had paid a $10 fee for Global Messaging up to 50 texts (lots more than we'd normally use when abroad). We had paid a $5.99 fee to AT&T to join their World Traveler service which lowers overseas calls to 99 cents a minute, a considerable savings over their standard European rate per minute.
We would only use Internet and email when we had Wi-Fi access (after shutting off Airplane Mode and re-activating whatever email address we wanted to use).
Assured that we'd done all we could to keep our smart phones smart when it came to controlling costs, we assiduously ferreted out free Wi-Fi hot spots to send and download email and to browse the web.
Even so, the data devils managed to outwit us, leading to the almost inevitable phone bill sticker shock when we got home. Not that the unexpected costs were anywhere near the multi-thousand dollar horror stories we'd read about during our "how to manage overseas cell costs" learning curve.
Nevertheless, it was frustrating to see charges for what we assumed would be no-charge free calls: a couple of calls made using AT&T's local French contact number on the back of AT&T's pre-paid card; using our credit card's international number to report a potentially lost card (they answered the ring with "American Express accepts collect calls", so why would we be charged for the rather lengthy call?); and a couple of calls to in-country toll-free numbers - doesn't toll-free mean there's no charge?
Naïve, weren't we? And here's why - every call involves roaming use of the host country's cell towers, a service that comes with a cost. A toll-free call needs a cell service to connect with the called number's service provider. You have to use the local cell system before you reach the local AT&T contact number.
Now suppose your phone rings and you choose not to answer. That's a missed call, right? No connection, no charge, right? Nope. There'll be a minimum one-minute charge, even if you don't answer and especially if the caller leaves a voice mail message (which could be more expensive if the caller is long-winded). And who knows how to disable voice mail? We didn't. But we do now after a courteous customer service rep at AT&T "educated" us about how the system works. And very generously offered to credit the call charges we were questioning when we saw the bill.
Cell calling overseas: complicated, confusing and, when the bill arrives, depressing.
Maybe the solution is to buy a cheap phone in Europe, put some euros in its account, tell your new phone number to everyone whose calls you'll happily answer, then relax. Or open a Skype account. Or keep your cell phone powered off.
Or just be carefully aware of how you use your cell - then cross your fingers and wait for the next phone bill after you return.
Maybe the surest idea is to leave it home in the first place. Just saying.