I think that even if you are in a US port such as Key West and you make a cell phone call from the ship you still can incur roaming charges. I was told it picks up the ships satellite, you have to actually make the call off the ship to not incur roaming fees. I have never made a call from the ship and told friends and family I will have my phone off. If there is an emergency they have the number of the cruise line who then can contact me. Wow I feel sorry for the $1,000 texting bill, ouch!