For all-inclusive resorts, most won’t charge for non-motorized sports, which includes everything from kayaking, snorkeling, and paddle-boating to tennis, basketball, and volleyball. Activities involving trips or lots of equipment — which can include golf, deep-sea fishing, horseback riding, and scuba diving — usually cost extra.
For cruises, especially newer ships, you won’t have to pay for most onboard activities like any sports, rock climbing, zip-lining, and use of the surf or skydiving simulators, where applicable. If you get off the ship, however, you’re on your own — unless you book an excursion through the cruise line.
For both, you’ll probably pay for all spa treatments and lengthy excursions, but not for use of the pools or fitness centers. With all these variables, it’s hard to make a definitive ruling, especially if you’re fine with sticking to the basic activities.