Here are several well-known all‑inclusive (or with all‑inclusive package options) beach resorts in Sri Lanka, with where they are, what their AI packages typically include, and a quick note on what to check before booking.

Top picks

• Heritance Ahungalla — Bentota / Ahungalla (southwest coast). Offers all‑inclusive and full‑board packages (buffet meals, beach/pool access, activities; seasonal promotions available). (heritancehotels.com)

• Centara Ceysands Resort & Spa — Bentota. Marketed with an All‑Inclusive option that usually covers breakfast/lunch/dinner at the main restaurant, selected beverages (local beer, spirits, wines during set hours), minibar replenishment and some discounts on a‑la‑carte outlets. Family friendly with kids’ club and watersports. (TropicalSky.com)

• Cinnamon Bey / Cinnamon Bey Beruwala — Beruwala (west coast, between Colombo and Bentota). Cinnamon runs “All‑Inclusive Escape” / all‑inclusive packages at this property (meals, snacks, selected drinks and certain outlets included). Good for beach access and multiple on‑site restaurants. (cinnamonhotels.com)

• Avani Kalutara (and nearby Anantara/Anantara Kalutara) — Kalutara. These resorts (Anantara/Avani group) offer all‑inclusive and full‑board packages at times — typically daily meals, snacks and a beverage package plus some activities and resort credits depending on the offer. The properties are lagoon/oceanfront and family oriented. (TropicalSky.com)

• Club Hotel Dolphin — Waikkal (north of Colombo). Often sold as an all‑inclusive resort by tour operators; packages usually include buffet meals, selected drinks, snacks and evening entertainment. Good for shorter trips from Colombo. (loveholidays.com)

What “all‑inclusive” usually covers (varies by hotel)

• Daily buffet or a‑la‑carte meals (breakfast, lunch, dinner).
• Selected house wines, local beers and spirits during set hours; soft drinks and snacks.
• Some water sports activities, kids’ club access, entertainment and pool/beach facilities (but many hotels exclude motorised activities or specialist services).
• Extras (spa treatments, premium imported drinks, some excursions, special a‑la‑carte restaurants) are often excluded or charged extra — always check the fine print. (TropicalSky.com)

Important booking tips

• Packages, inclusions and prices change frequently — confirm directly with the hotel or a reliable OTA before booking. Many hotels run seasonal AI offers (check validity dates and blackout periods). (heritancehotels.com)
• Alcohol service can be restricted on full‑moon Poya days and some religious festivals in Sri Lanka; properties will note this in their terms. (TropicalSky.com)
• If you want true “all‑inclusive” (including premium drinks, shore excursions, transfers etc.) ask for an explicit, line‑by‑line inclusions list from the hotel — different hotels label packages differently. (TropicalSky.com)

Would you like:

• A short list filtered by travel time from Bandaranaike Airport (Colombo) or by region (south vs west coast)?
• Live availability/prices for specific dates (I can check current rates and package details)?

If you want me to check availability or compare packages for exact dates, tell me your travel dates and whether you prefer family, adults‑only, luxury, or budget options and I’ll pull current offers.