Coco Plum Island Resort

Belize's couples-only private island. 16 cabanas, no children under any policy, three meals a day with the chef included, and a score of 98.5 across the index's eight data sources. This is what "adults-only" means when the marketing isn't softened — there's no 18+ wing, no occasional family weekend, no "we just don't market to families." The property is structurally couples-only by capacity and policy both.

The logistics are part of the product. Coco Plum is a 15-minute water taxi from Dangriga on the Belize mainland — small-plane to Dangriga from Belize City, then the boat. That two-leg transfer is the gate that keeps the property quiet, and travelers who can't tolerate the water taxi will be unhappy. Internet is satisfactory but limited.

What you're paying for: the rarest combination in all-inclusive travel — strict couples-only, sub-50-room private island, and a price point (roughly half what The Aerial costs) that's reachable for a regular honeymoon budget rather than a milestone-event one. The dive and snorkel program off the property is genuinely first-rate. If the brief is "honeymoon, strictest interpretation, no compromises," this is the answer.