For the Norwegian Cruise Line Pride of America, the tour picks up passengers from this ship every Sunday. It's actually quite close to where the tour naturally begins. Pick-up time is around 7:30-8 am, and the van will be there when you arrive and disembark the ship. Please ensure you choose the first day you're on Maui (Sunday), since the tour concludes in the evening (around 4:30-6 pm). If you can only do Monday (when you would need to be back by 5 pm at the latest), you would need to book a private tour (just select 8+ people when booking) and the pickup time would be 6:15 am in order to ensure you are back in time. In the unlikely case the ship does not arrive as scheduled, you will receive a full tour refund if you can't reschedule.
If you're coming in to port at Kahului on a Carnival cruise, it depends on the schedule, but if it arrives at 8 am or later, you would need to do a private tour. Depending on the pick-up time, the required return time, and the pace of the tour, it may have to return shortly after Hana rather than do the full loop since the backside road should not be driven in the dark. In general, return time to Kahului is around 6:30 pm, or 4:30-5 pm if doing modified tour that turns around near Hana.
For cruises arriving in Lahaina, pick-up is at 7:15 am, so it's doable only with cruises that arrive at 6 am, since it usually takes about a hour to get to shore. Note you do not return until around 7 pm. If this does not fit your cruise ship schedule, you could do a private tour. If your cruise ship arrives in the morning after 7 am and doesn't leave in the evening or leaves 8:30 pm or later, your private tour would do a modified version: during the summer months the normal itinerary with perhaps just a little less time at some stops, or other times of the year turning around near Hana as described above. It would return to Lahaina around 7-8 pm. If your cruise leaves before 8 pm that day, your private tour would do a modified itinerary in which it is the same until the tour reaches Hana, after which the tour turns around (rather than go all the way around). Therefore, in the itinerary below the last stop is Hana Bay Black Sand Beach, or occasionally Hamoa Beach (time permitting). If interested in a private tour, see FAQ below, and please note at checkout the cruise ship you will be arriving on.