Every coaching team runs into the same math sooner or later. Members keep coming, the team doesn't grow at the same pace, and someone asks whether some of those one-on-one sessions could be groups. It's a fair question, and the research gives a clearer answer than most people expect.
Here's what the trials found, where the savings really come from, and how we'd decide which members go where.
What research says about group coaching vs. one-on-one
The strongest evidence comes from weight management, where researchers have tested the same program delivered both ways. A 2022 review of 10 trials with 2,169 adults found people in groups lost about 1.3 kg more than people seen one-on-one by the end of follow-up. Group members were also more likely to lose at least 5% of their body weight, and they dropped out at about the same rate.
In other programs it's a tie, not a win. A Cochrane review of smoking cessation found no difference between group programs and individual counseling of similar intensity, across 6 trials and 980 people. The authors were careful to add that there isn't enough evidence to say whether groups are more effective or more cost-effective than intensive one-on-one support.
Diabetes education points the same way. A 2022 meta-analysis of 14 trials in type 2 diabetes found no difference in blood sugar control between group and individual education, and group members reported better quality of life and knowledge.
Where the savings come from
The basic math is easy. A one-hour session with ten members is six minutes of coach time each, before prep and follow-up. It's the same coaching hour reaching ten people instead of one.
One trial in the 2022 review measured it directly.
One trial, reported in Street & Avenell, 2022
The group version also cost less to run overall. But the savings aren't automatic. Another trial in the same review found the group version cost more per kilogram lost once members' own time was counted, so cheaper for you isn't always cheaper for the member.
Groups also carry costs a one-on-one calendar doesn't. You need enough people ready to start at the same time, a time slot most of them can make, and a plan for when the group thins out. And the review points to research showing that how well a group works depends heavily on the person leading it, which means choosing and training facilitators.
When groups pay off
This is our view, from running coaching programs. Groups earn their place when four things are true.
Members share a goal
Groups work when the room is working on the same thing: a weight program, quitting tobacco, a new diabetes diagnosis. A mixed group spends its first sessions looking for common ground.
Enough people can start together
You need a steady flow of members ready to begin at once. A group of three that waits a month to fill loses people before it starts.
The program has a set path
Groups suit programs with a curriculum, where each session has a topic and everyone moves through it together. Open-ended coaching, where each member sets the agenda, fits a group badly.
Your coach can run a room
Leading a group isn't one-on-one coaching with more people on the call. It means drawing out quiet members, keeping one person from taking over, and turning what members share into the lesson. Train for it before you schedule it.
When one-on-one is the better call
Keep one-on-one for what a group can't hold. That's the member dealing with something they won't say in front of others, or whose health is complicated enough that group advice doesn't fit. It's also anyone who raises something outside your coach's scope of practice and needs a referral, which is a private conversation. And it's members whose work or caregiving schedule can't fit a fixed weekly time.
One-on-one also earns its cost at two points in any program: the first conversation, where a coach learns what the member wants, and the check-in when someone starts to slip.
A mix usually beats either one
Most teams don't have to choose. The setup we'd start with is a one-on-one intake, a group core for members with the same goal, and short one-on-one check-ins for anyone who falls behind. It's one of the more practical ways to scale a coaching team while keeping every member in real contact with a coach.
Where Avidon fits
A group meets once a week. Most of the work happens in between. In Avidon, team challenges give a group something to do together between meetings, and member messaging lets you segment by course or challenge activity and schedule texts and emails, so a member who missed Tuesday's session hears from you by Wednesday.
That between-session contact matters. In Avidon's 300-participant controlled study, program completion was:
If you're building a coaching business that uses both formats, see how Avidon works for coaching companies.
