Avantika in St. Maarten, a Thai restaurant and lounge, has a happy hour every Friday from 3–6 PM, half priced drinks and appetizers
Avantika - linkTortuga, by the pool at Royal Islander's La Plage, Maho, has a happy hour every day from 3-5, right on the water, good drinks and food and great place to watch the planes come in to land
Tortuga - linkLagoonies in Cole Bay, on the lagoon, happy hour is 5-6
Lagoonies - link