Short answer first — clear expectations:

• True “all‑inclusive” resorts (meals + drinks + many on‑site activities included) are uncommon inside Colombo city itself. Colombo’s large hotels instead typically offer family packages / kids‑eat‑free or breakfast/half‑board offers. (familyvacationvibes.com)

If you want all‑inclusive (full board + drinks) look just outside Colombo — if you want a city stay with family perks, see the Colombo options below.

A. Colombo (city hotels with family packages / family perks — NOT full all‑inclusive)

• Cinnamon Grand Colombo — regular family offers and packages (kids’ options, family dining/gifts; good for families in the city). (cinnamonhotels.com)
• Shangri‑La Colombo — family amenities (kids’ play space/Adventure Zone) and kids dine complimentary/discounted at the all‑day restaurant. (shangri-la.com)
• Hilton Colombo (Hilton Colombo Residences) — has offered “Family Fun Weekend” style packages and family suite options. Good for short family city breaks. (archives1.dailynews.lk)
• Taj Samudra / Cinnamon Lakeside / Cinnamon Life (City of Dreams) — these large Colombo hotels commonly run family promotions (kids stay/dine deals, interconnecting rooms, family experiences). Check the hotel offers pages when booking. (tajhotels.com)

B. Nearby all‑inclusive (true all‑inclusive or all‑inclusive packages) — short drive from Colombo

• Cinnamon Bey Beruwala (Beruwala) — advertises an “All‑Inclusive Escape by the beach” and family offers; roughly ~1–1.5 hours south of Colombo depending on traffic. Good for beach + easy transfer. (cinnamonhotels.com)
• Avani Kalutara / Anantara Kalutara area (Kalutara) — Avani Kalutara offers all‑inclusive rate options and family facilities (kids’ club, pools); about ~1 hour from Colombo. (tropicalsky.com)
• Anantara Peace Haven Tangalle — offers explicit “All Inclusive Indulgence” packages and a kids/teens club; further away (several hours’ drive — better as a dedicated beach stay or combined with southern coast travel). (anantara.com)

Practical notes and tips

• If you need genuine unlimited food/drink/activity inclusions, pick one of the coastal resorts above — confirm exact inclusions (which restaurants, alcohol brands, times, excursions) before booking because packages vary. (cinnamonhotels.com)
• For stays inside Colombo (business/city sightseeing) the city hotels’ family packages usually include breakfast, kids’ meals or discounts, kids’ clubs, connecting rooms and sometimes credits/activities — they are not the same as beach resort all‑inclusive plans. (cinnamonhotels.com)
• Transfer times: Colombo → Kalutara/ Beruwala is typically ~1–1.5 hours by road; Colombo → Tangalle is significantly longer (3.5–5+ hours depending on route/traffic). Traffic can add substantial time — factor that into plans.

If you’d like, I can:

• Check current all‑inclusive package rates and exact inclusions at any of the properties above for specific dates (I can look availability and sample prices), or
• Suggest the best pick depending on whether you prioritize minimal travel (stay in Colombo) or a true all‑inclusive beach experience (nearby resorts).

Which would you prefer — a city family package or a beach all‑inclusive resort?