How Many Friends Do You Really Need?

If your goal is simply to mitigate the harmful impact loneliness can have on your health, what matters most is having at least one important person in your life — whether that’s a partner, a parent, a friend or someone else, said Jeffrey Hall, a professor of communication studies at the University of Kansas. 

The best-known theory of how many friends people can (though not necessarily should) have comes from British psychologist and anthropologist Robin Dunbar. What has come to be known as Dunbar’s number contends that humans are only cognitively able to maintain about 150 connections at once (subsequent research has put the number higher). That includes an inner circle of about five close friends, followed by larger concentric circles of more casual types of friends.

The amount of time you actually spend with your friends matters, too. Dr. Hall’s research suggests that on average, very close friendships tend to take around 200 hours to develop. Quantity and quality go hand-in-hand.

Catherine Pearson writing in the New York Times