I usually call at least one credit card's security line and let them know my out of country dates. I add a couple days at the end in case there is a weather or mechanical day on the once a day plane and I have to pay an extra night for the hotel.

I have never called about my ATM and have used my ATM card for cash at the airport and banks in Europe and Asia and never had it declined.

When telling the security person the countries they might see charges coming in from, don't forget to include your major international connecting airport countries. On the way home you might find a perfect little item in the NRT or AMS gift shop after you change your money, or in a country where you never had any local currency. Or you might get stuck there by a snowstorm or volcano and need to pay for your own hotel. You might not plan to spend in that connecting country but end up doing so.