Here are strong hotel choices in Colombo for business conferences, grouped by the kind/size of event they’re best for and with quick notes you can use when you request proposals.

Top picks (with why they’re good)

• Shangri‑La Colombo — best for very large, flexible ballrooms (huge main ballroom that can be sub‑divide; very large theatre/banquet capacities). Good AV, multiple breakout rooms and outdoor lawn options. (shangri-la.com)
• Taj Samudra — traditional, well‑established MICE hotel with multiple large ballrooms (Samudra Ballroom, Grand Marquee) and lawns; suitable for conferences up to ~1,000+ depending on setup. (tajhotels.com)
• Hilton Colombo (and Hilton Colombo Residences) — modern pillar‑free ballroom(s), professional event team and up to ~1,000+ in largest setups; good for corporate conferences and conventions. (hilton.com)
• Cinnamon Life Integrated Resort — new/large integrated resort with very large meeting/exhibit space (massive total meeting/exhibit area), built for large conferences and trade shows. (cvent.com)
• Cinnamon Lakeside Colombo — strong choice for big events and evening functions (several ballrooms, unique floating venue and large banquet capacity); solid MICE services. (cinnamonhotels.com)
• Cinnamon Grand Colombo — traditional large hotel with a range of ballrooms and meeting rooms (Oak Room and other rooms) good for conferences, launches and multi‑room events. (cinnamonhotels.com)
• Galle Face Hotel — heritage property with well‑appointed meeting rooms and ballrooms up to a few hundred; excellent for executive conferences and high‑profile events. (gallefacehotel.com)
• Mövenpick Hotel Colombo — modern mid‑to‑large MICE facilities (two ballrooms and several meeting rooms) for conferences ~50–200 people per room or combined. (newsvoir.com)
• The Kingsbury Colombo — strong for board meetings, executive retreats and smaller breakout/boardrooms; good harbourfront location and private meeting spaces. (thekingsburyhotel.com)

Which hotel to choose by conference size

• Small executive meetings / boardroom (10–50): The Kingsbury, Galle Face Hotel, Cinnamon Grand (boardrooms). (thekingsburyhotel.com)
• Medium conferences (50–250): Mövenpick, Cinnamon Lakeside, Hilton Colombo, Taj Samudra (smaller ballrooms). (newsvoir.com)
• Large conferences / banquets (250–1,000+): Taj Samudra, Shangri‑La Colombo, Hilton (largest halls), Cinnamon Lakeside; Cinnamon Life or Taj for very large trade shows or gala marquis. (tajhotels.com)

Quick checklist to include in your RFP / site visit request

• Exact capacities by seating style (theatre, classroom, banquet), and whether rooms are divisible. (Hotels above publish floor plans and capacities on their MICE pages.) (shangri-la.com)
• AV package details (projectors, PA, mics, staging, on‑site tech support) and any extra AV fees. (gallefacehotel.com)
• Internet bandwidth / dedicated event Wi‑Fi SLA and data limits. (gallefacehotel.com)
• Accommodation block availability (number of rooms, room types, negotiated rates) and transport options to Bandaranaike International Airport. (hilton.com)
• F&B (delegate package pricing, dietary options) and breakout catering logistics. (cinnamonhotels.azurewebsites.net)
• On‑site event manager, security, insurance requirements and cancellation/force‑majeure terms. (cinnamonhotels.azurewebsites.net)

If you’d like, I can:

• Narrow this to hotels in a specific Colombo neighbourhood (Fort/Galle Face vs. Port City), or
• Produce a short RFP template you can send to 3–5 shortlisted hotels (includes questions on AV, capacity, rates, contract terms), or
• Compare rates and availability for specific dates (I’ll need the dates and expected delegate count to check availability/pricing).

Which of those would you like next?