Great — here are top spa hotels in Sri Lanka known for outstanding wellness, relaxing settings, and high-quality treatments. I’ve noted where each is, what makes its spa special, who it’s best for, and a rough price tier. Sources for each entry are linked after the description.

1. Santani Wellness Resort (near Kandy) — destination spa focused on Ayurveda, hydrotherapy and personalised wellness programmes; tri-level spa tucked into hillside, daily yoga/meditation and bespoke wellness cuisine. Ideal for a multi‑day reset and serious wellness travellers. Price: high (luxury retreat). (santani.com)

2. Amanwella (Tangalle / south coast) — intimate Aman resort with oceanfront treatment pavilions, Ayurvedic-inspired treatments, yoga by the sea and a very calm, minimalist setting (private‑pool suites). Best for couples and ocean-side tranquillity. Price: very high (luxury). (luxewellnessclub.com)

3. Heritance Kandalama (Dambulla / Cultural Triangle) — architecturally striking hotel overlooking Kandalama Lake and Sigiriya, with a well‑regarded spa offering Ayurvedic and Western treatments, steam/sauna and yoga — good for combining culture and relaxation. Price: mid–high (upscale resort). (heritancehotels.com)

4. Anantara Peace Haven Tangalle (Tangalle) — large ocean‑cliff resort with an award‑winning Anantara Spa offering a wide range of Ayurvedic programmes, signature massages, and multi‑day wellness packages; strong facilities (yoga pavilion, Ayurvedic practitioners). Best for resort comforts + spa variety. Price: mid–high. (Anantara.com)

5. Ulagalla by Uga Escapes (Anuradhapura / Cultural Triangle) — boutique eco‑luxury villas with an atmospheric, “hidden” spa (open‑air/earthy design), traditional Ayurvedic treatments and private spa pavilions; excellent for privacy and nature immersion. Price: high (boutique luxury). (theluxevoyager.com)

6. Jetwing Vil Uyana (near Sigiriya) — eco‑friendly wetland property with nature‑integrated spa treatments, Ayurvedic and Western therapies, and serene private villas — great if you want spa time within a wildlife/nature setting. Price: mid–high. (en.wikipedia.org)

7. Ceylon Tea Trails (Nuwara Eliya / tea country) — converted tea‑planter bungalows with personalised wellness treatments, gentle spa services, massages and very peaceful hill‑station setting — ideal for combining tea‑country walks with restorative treatments. Price: high (luxury countryside). (countrylife.co.uk)

8. Saman Villas (Bentota / southwest coast) — an award‑winning boutique beach hotel with a strong spa programme (treatment rooms, sauna, hot tub) and a very private, romantic atmosphere; good for beachside relaxation with spa pampering. Price: mid–high (boutique luxury). (en.wikipedia.org)

Quick tips for choosing:

• Pick Santani or Anantara for structured, multi‑day wellness/Ayurveda programmes. (santani.com)
• Choose Amanwella or Saman Villas for intimate, luxury beachside spa time. (luxewellnessclub.com)
• If you want nature/ruins plus spa (quiet + sights), consider Heritance Kandalama, Vil Uyana or Ulagalla. (heritancehotels.com)

If you want, I can:

• narrow these to a particular region (south coast, hill country, Cultural Triangle),
• compare package prices for your travel dates, or
• suggest an itinerary that pairs spa days with sightseeing.