The island has a wonderful climate all year round. Temperatures are between 25 and 30 degrees at any time of the year. The atmosphere is pleasant due to the Pacific trade winds. That blow throughout the year.
Despite these data. The best time to visit Bora Bora is from May to October. This does not mean that the rest of the year cannot pass. But it is true that between November and April you can find quite strong winds. That can make your stay on the island rather unpleasant. May, June, September and October. They have the best combination of time. And availableness of hotel rooms.