What are some typical ways to socialize, either with local people or with other expatriates? Are there groups or clubs that you can recommend?
People tend to social informally. It's a friendly community, both in the Embassy community and the larger expat community. - Apr 2020
See above - IEA. Many hotels also offer events.
The Community Liaison Office (CLO) at the embassy is wonderful at coordinating things for the American community. - Sep 2017
There is a International Expat Assiciation (IEA) that meets monthly. This is a good place to start. There are book clubs, concerts, parties and any number of activities that if you keep your eye out for, will connect you with many people. Of course many people find themselves at a hotel for the use of their pool or at the embassy recreation center on the weekend to socialize and eat. It is what you make it. - Mar 2017
Mostly expat groups or private parties. Clubs/discos are here as are many restaurants. - Sep 2013
Limited, but Colombo hotels are very vibrant. Night clubs are mafia-controlled. - Sep 2012
There are a couple of movie theaters in Colombo, although most movies are Bollywood. There is always a weirdly timed intermission in the movies. - Dec 2011
Restaurants, bars, bbqs, private parties, swimming. - Feb 2010
As I said, the N&G Golfing Society occupied most of my time on weekends and the friends I made led to other social events or outings. A N&G golf outing to Kandy is a rowdy bus trip and a fun-filled dinner. Some golf was played but I have trouble remembering it. I would not recommend going to casinos other than to look and leave. - Sep 2008