St Lucia is the most-booked honeymoon island in the Eastern Caribbean, and it earns the position. The Pitons are the photograph. Sandals runs three properties here, more than on any other Sandals island. Independent luxury (Jade Mountain, Cap Maison, Ladera, Sugar Beach) covers the higher end.
The short answer
If you want the Sandals all-inclusive experience: Sandals Grande St Lucian for peninsula walkability + overwater bungalows, Sandals Halcyon Beach for quiet Sandals, Sandals Regency La Toc for the largest estate and hillside ocean views.
If you want Piton-view iconic photography: Jade Mountain is the pick if the budget stretches to $1,200+ per night, Ladera for two-thirds of the experience at a third of the price, Sugar Beach A Viceroy for the exact between-the-Pitons address.
If you want food and quiet without the Piton view: Cap Maison in Cap Estate is under the radar for honeymoons and the Cliff at Cap kitchen is one of the highest food ceilings on the island.
Which of the three Sandals St Lucia
Grande if you want energy and walkability. Halcyon if you want the quieter adult-only feel. Regency La Toc if you want the estate size and hillside layout. Grande has the overwater bungalows, so it wins the iconic-honeymoon-photograph category by default.
Check honeymoon dates at Sandals Grande St LucianWhen to book
Best months for a St Lucia honeymoon are January through April (dry, high demand, book 9+ months out). May and June are the underrated shoulder months (dry-enough, jazz festival, prices 20 to 30 percent below peak). Avoid mid-August through mid-October (hurricane peak). September has the lowest prices and the highest risk; travel insurance is not optional.
Split-stay vs single-base
The split-stay case: three nights Rodney Bay (Sandals Grande for walkable + overwater), four nights Soufrière (Jade Mountain or Ladera for Piton view). The single-base case: seven nights at Cap Maison or Sugar Beach if you would rather unpack once and treat the Pitons as a day excursion. Both work. Split-stay wins if you have never been to St Lucia.