How do you send mail to someone on a cruise ship?

To send mail to someone on a cruise ship, address the envelope with the recipient's name, the ship's name, and the cruise line, along with the ship's current port of call or scheduled itinerary. It's important to include the specific sailing dates, if possible. Mail can be sent to the cruise line's headquarters or port facility, where it will be delivered to the ship. Additionally, check with the cruise line for any specific mailing instructions or guidelines.