What’s the ideal team size? Is there such a thing as an ideal team size?

It’s something I’ve been thinking through since I’m part of various non-profit boards that are each wanting to recruit new members. And an obvious question is how many people do we want on the team? What would be the ideal board size? Is there an ideal board size, or even an ideal team size?

Teams can vary hugely in the numbers of people on them, but perhaps there are some common characteristics. And please note that I’m talking here about teams as opposed to organisations.

A team is group of people working on a common goal, with a relatively flat hierarchy. There will normally be one person who chairs the team, and maybe a few people with more seniority than others. But all the team members will relate to the one chair as their line manager. I’m not talking here about larger groups (e.g. companies) that are actually split up into several smaller teams, units or departments. I’m asking, for each of those units or departments, is there an ideal team size?

Here’s what I’ve been thinking:

  • Modern Politics: Some of the largest teams that relate to one chair are government cabinets. The UK cabinet is capped at 22 people. But this is generally considered far too large as an effective team size. In any team meeting there is not enough time for each team member to make a meaningful contribution.
  • Historic Politics: But cabinets have grown this large since governments over time gradually took on more responsibilities. And more responsibilities means more departments, more ministers, and since every minister demands a seat at the top table, it means a bigger cabinet. But historically cabinet government was much smaller than this. I’m currently reading a biography of Abraham Lincoln, and he led a cabinet of 8 people (including himself). A much smaller team, and perhaps a much more effective model.
  • Sports: Many sports have teams of 11 (football, cricket, field hockey, American football). Some go up to 15 (rugby union). Then at the smaller end of the scale there are nine people in a baseball team, seven on a netball team, six each on volleyball and ice hockey teams, and just five people on a basketball team.
  • Religion: Jesus called 12 disciples to follow him. That’s a team of 13 people in total (when you include him). One of those people betrayed Jesus and let the whole team down.
  • Business: Most large businesses have senior executive teams of around 5-9 people. That’s small enough for everyone to have a clear role and be able to participate, but large enough to have a community of people who will bring energy and creativity to each other.

In my experience, the best team I’ve ever been part of had eight people. We each had a clear role, we were able to get to know each other really well individually, and we had great fun together as a group. And we all worked incredibly hard to help the team achieve its goals.

So is there an ideal team size? I’d say that over 15 becomes far too unmanageable, and for most leaders over 10 is probably quite large (unless you are Jesus, or you’re playing a specific team sport). For many other teams trying to work together, 5-9 often becomes the optimum size. Smaller than that and you may find yourself with low team energy, but larger than that you may find people zone out, and don’t contribute as much as they otherwise could do.

For my various boards, I’m looking at seven or eight as being the optimum number. And that means we have a spare space when a brilliant person suddenly appears, so we won’t miss out on the potential they can add.

Mark Williamson works as a director of One Rock. He’s an experienced leadership trainer, author of biographies on John Wesley and William Wilberforce, and is also passionate about praying for London. He enjoys good films, good food, and going for long walks with his wife Joanna. You can follow him on Twitter @markonerock.