Here are well-known hotels in Colombo that offer private event-hosting facilities (ballrooms, lawns, boardrooms and dedicated events teams). I’ve listed typical spaces/capacities and the hotel events/contact page for each so you can check availability and packages.

• Shangri‑La Colombo — very large pillar‑free ballroom (up to ~1,500 banquet / ~2,100 theatre), smaller ballrooms, spice‑themed breakout rooms and an outdoor lawn; suited for large conferences, weddings and private gala events. (shangri-la.com)

• Taj Samudra, Colombo — multiple ballrooms and landscaped lawns (venues from intimate boardrooms up to lawns/ballrooms for several hundred to ~2,000 for marquee-style events); good for conferences, weddings and beachfront/private functions. (tajhotels.com)

• Cinnamon Grand Colombo — large Oak Room ballroom and several smaller meeting/banquet rooms (suitable for weddings, conferences and private dinners); flexible setups from small boardrooms to large banquets. (cinnamonhotels.com)

• Cinnamon Lakeside Colombo — major ballrooms (King’s Court, Queen’s Court), lakeside lawns and floating/unique venues; common choice for weddings, corporate galas and product launches. (cinnamonhotels.com)

• The Kingsbury Colombo — multiple banquet halls and boardrooms (Balmoral ballroom up to ~500 guests; several mid‑sized rooms and private dining/meeting rooms); good for large social events and private corporate meetings. (thekingsburyhotel.com)

• Hilton Colombo (and Hilton Colombo Residences) — pillar‑free ballroom space and smaller meeting rooms (ballrooms that can host several hundreds; full events team and AV support); suitable for business conferences and private functions. (hilton.com)

• Mövenpick Hotel Colombo (Accor) — two banquet/ballroom venues plus multiple meeting rooms and boardrooms (options for intimate private events up to a couple of hundred); rooftop/terrace options for smaller private gatherings. (movenpick.accor.com)

• Galle Face Hotel — historic property with several ballrooms, the Chequerboard lawn (oceanfront) and multiple meeting rooms (venues from small boardrooms to ballrooms for a few hundred or outdoor weddings up to ~1,000); iconic seafront event settings. (gallefacehotel.com)

• Galadari Hotel Colombo — Grand Ballroom and a variety of banquet/meeting rooms and lawns with private‑event packages; commonly used for weddings, corporate events and product launches. (galadarihotel.lk)

• Cinnamon Life / Cinnamon Life City of Dreams complex — large modern convention/ballroom spaces and a range of meeting rooms (designed for big MICE events, conferences and large private functions). (cvent.com)

Notes and next steps

• Capacities and layouts vary by room and by preferred seating (banquet, theatre, cocktail). Always confirm the exact capacity, AV equipment, catering and privacy/curfew rules with the hotel event/sales team before booking.
• I’ve cited each hotel’s events/venue page so you can view floor plans and contact details directly. If you want, I can: (a) shortlist venues that match a specific guest count (e.g., 20 / 100 / 300), (b) compare pricing and menu sample packages (if you give a date or budget), or (c) pull contact details and the events‑email/phone for any 2–3 hotels you pick.