French swim brand Eres’s year-round shop carries high-fashion beachwear and lingerie (55 Main St., East Hampton; 631-604-5544).
Stuart Weitzman’s boutique excels in resort footwear, from espadrilles to jellies to stilettos (53 the Circle, East Hampton; 631-324-5624; opens 5/25).
The 600-square-foot Oak pop-up sells home décor and exclusive beach gear from Acne and Alexander Wang (Harbor Walk, Fire Island Pines; 631-597-6813).
Cynthia Rowley’s shack debuts her Roxy-collaborated wetsuit line, plus all manner of hostess gifts (696 Montauk Hwy., Montauk; 631-668-8077; opens 5/27).
Pick up beach blankets, Thom Dolan bikinis, surf trunks, and other pool-deck duds at Steven Alan’s seasonal bazaar (75 Main St., East Hampton; 631-604-1726).
The Lacoste surfside shop brims with gator-logoed sun hats, pique polos, chambray dresses, and towels (48 Main St., East Hampton; 631-324-7333).
Sunbarth is selling Orlebar Brown and Sundek swim trunks, Ruby helmets, and shades throughout the summer (53 Jobs Ln., Southampton; 631-873-4121).