Here are top-rated seaside resorts in Sri Lanka (covering south, east and west coasts, a range of budgets and travel styles). Short notes on why each is highly rated and where it’s located.

• Cape Weligama (Weligama / south coast) — Cliff-top Relais & Châteaux resort with villas, dramatic ocean views, intimate service and easy access to surf/whale‑watching around Galle. Great for luxury/romance. (tripadvisor.com)

• Amanwella (Tangalle / south coast) — Minimalist, very private beachfront suites (many with plunge pools), exceptional beach and calm vibe — a top choice for quiet luxury beach stays. (cntravellerme.com)

• Anantara Peace Haven Tangalle Resort (Tangalle / south coast) — Large beachfront property with villas and pool villas, strong family/kids facilities, spa and varied dining; popular for both families and couples. (booking.com)

• Jetwing Lighthouse (Galle / south coast) — Iconic Geoffrey Bawa–designed hotel on a rocky promontory near Galle Fort — admired for architecture, sea views and proximity to historic Galle. Good for culture + coast. (en.wikipedia.org)

• The Fortress Resort & Spa (Koggala / south coast) — Boutique luxury resort with stylish rooms, award‑winning dining and an oceanfront location near Galle; often praised for service and spa. (en.wikipedia.org)

• Amangalla (Galle Fort / south coast) — Historic, high‑end Aman property inside UNESCO‑listed Galle Fort (more “heritage” than wide sandy beach but excellent coastal access and old‑world charm). (en.wikipedia.org)

• Wild Coast Tented Lodge (near Yala / south‑east coast) — Luxury beachfront glamping by Resplendent Ceylon, combining tented “cocoons” with safari and ocean — excellent for nature + beach. (resplendentceylon.com, theluxurytravelexpert.com)

• Karpaha Sands (Kalkudah / east coast) — Small, low‑impact luxury tented suites on a long, calm east‑coast beach (Kalkudah/Pasikudah area) — ideal for privacy, swimming and sunsets (east coast best in May–Oct). (karpahasands.com, travelweekly.com.au)

• Weligama Bay Marriott Resort & Spa (Weligama / south coast) — Large modern beachfront resort with family facilities, Quan spa and direct access to one of the south coast’s best surf beaches. Good mid‑to‑upper tier option. (tripadvisor.com, marriott.com)

• Heritance Ahungalla (Ahungalla / west‑south coast) — Long beachfront property (Geoffrey Bawa influence), solid facilities, popular with families and couples looking for value and a classic Sri Lanka beach hotel. (tripadvisor.com)

• Shangri‑La Hambantota (Hambantota / south coast) — Large resort with its own 18‑hole golf course, family waterpark and Ayurveda spa — good for families and activity‑focused stays. (shangri-la.com, booking.com)

• Trinco Blu by Cinnamon (Trincomalee / east coast) — Well‑reviewed beachfront option on the calm northeast coast, handy for snorkeling/Pigeon Island and whale/dolphin excursions in season. (cinnamonhotels.com, booking.com)

Quick timing tip — Sri Lanka has two main coastal seasons: the south/west coast is best roughly November–April; the east coast (Trincomalee/Pasikudah/Kalkudah) is best roughly May–October. Plan locations by season for calmer seas and swimming. (thetimes.co.uk)

If you want, I can sort these by exact travel dates, budget, or travel style (honeymoon, family, surfing, wildlife) and build a short itinerary or check current rates/availability.