How Many Friends Do You Really Need At Work?

For a start, friends are proven to be beneficial in improving our performance and overall well-being. And crucially, friends at work make it much more fun.

But the number of friends we need is a totally different question. A look at the research suggests there are some universal limits on friendship.

Let us share what we learned from the research—and from visiting the world's most progressive workplaces.

Dunbar and friends

Diving into this topic brings you, sooner or later, to the work of British evolutionary psychologist Robin Dunbar (and his academic friends!). They speculated we only have the capacity to manage social relationships up to a certain number.

After extrapolating group sizes of primate communities and human society, they estimated this number at around 150 people. This is the so-called Dunbar number. It gained attention in popular media and is sometimes said to be the limit of people one person can have close personal relationships with.

It also means 150 is the magic number for groups where everyone still knows each other well enough to maintain social contact. Dunbar found many examples: from ancient groups of hunter-gatherers to military troops of the Spartans, in the Roman Empire, in 16th century Spain, and in the 20th century Soviet Union.

Dunbar's numbers

But 150 was not the only magic number Dunbar came up with. He identified a sequence of numbers that pointed to four layers in social groups; these being 5, 15, 50 & 150. These numbers represent layers of friends like the rings of a union.

Note the number of friends in each layer increases as we move up the hierarchy, and all are related by a factor of approximately three.

You should not, however, take the exact numbers too seriously. There is variance in the data. What the numbers stand for, however, needs to be taken much more seriously. Here we go:

5 extremely close friends

Dunbar and friends found there is, at any one time, a core group of extremely close friends with whom we share our strongest relationships. This first layer is of those we are closest to and care most about. This core group is only about 5 friends.

We have seen this number in practice as well. For example, in the maximum size of Handelsbanken's local branches (6 people) and the maximum team size at Basecamp (3 people)

15 close friends

The second layer is a group of friends with whom you enjoy spending meaningful time, but who are not as intimate as your extremely close friends. These are friends you would invite to dinner at your home, or turn to in case of need.

This close group includes about 15 friends. We have seen this number in practice in, for example, the maximum size of Buurtzorg's self-organizing teams (12 people), the average size of Haier's microenterprises (circa 10-15 people), and the size of Spotify's "Squads" (circa 12 people).

50 friends

The third layer is made up of people you call friends but do not see that often. You might not invite them to dinner at your home, but you would invite them to a party.

This acquaintance group consists of about 50 friends. We saw this number in practice in the maximum size of the democratically run law firm BvdV (circa 30 people) and the average size of departments at Spotify called "Tribes" (circa 40 people).

150 casual friends

The final layer is a group you might refer to as casual friends. This layer defines more or less the limits of your personal social horizon as far as friendship is concerned. These are people whose names you know, and with whom remain in social contact.

This social group consists of about 150 friends. We see this number in practice, for example, in the maximum plant size at W.L. Gore & Associates (150 people), and the maximum size of departments at Spotify called "Tribes" (150 people).

Increasing group size beyond this number will result in a significant loss of social stability, coherence, and connectivity. Ultimately it will lead to the disintegration of the group. And that is something you don't want to happen, as social relationships are integral to performance.

Your friends at work

Dunbar and his friends give us guidance in designing workplaces around the number of friends we can hold relationships with. Following their advice, we should keep teams small, and preferably between 5 and 15 people.

The same counts for departments, locations, and plants. Keep them small, preferably around 50 people. But perhaps more importantly, never let your departments, locations, or plants exceed the magic number!

Want more?

Want to dive into Dunbar’s academic work? Then read his book ‘How many friends does one person need?’, or try the landmark Science publication ‘Evolution in the Social Brain”.

But for now: what are your thoughts? Would splitting big departments into smaller ones help? Will smaller units help to boost motivation? Drop your thoughts in the comments below.