Not enough information. Your plan may include Mexico, or it's a low cost add on, but you didn't provide your plan name. Keep your phone in airplane mode on the ship. Cruise ships have satellite cellular and it's horribly expensive.
Staying connected on your trip is always a big deal. We want to make sure you'll be able to fully enjoy your service while you're gone. We're glad to help. What cruise will you be taking? What calling plan do you have?