What Size Should a Book Club Be? Finding the Right Number of Members

What Size Should a Book Club Be?

The ideal book club has 8–12 active, regularly attending members. If you're building your roster, invite 10–15 people to account for the reality that 25–35% of members will miss any given meeting due to scheduling conflicts, illness, travel, or simply not finishing the book. This means your actual discussion group will naturally settle around 8–10 people per meeting—the range that group dynamics research consistently identifies as optimal for structured conversation.

This isn't an arbitrary number. It emerges from decades of research on small group communication, and the data is remarkably consistent across academic studies, book club surveys, and community management literature. Below, we break down what the research says, how different sizes affect discussion quality, and how to manage your club's membership at every scale.

The Research Behind Optimal Group Size

The foundational research comes from organizational psychologist J. Richard Hackman, whose work at Harvard on team effectiveness found that groups of 6–10 people consistently outperform both smaller and larger groups on tasks requiring discussion and consensus. For book clubs specifically, the dynamics map closely to what Hackman observed in other deliberative settings.

A 2023 study published in the journal Group Dynamics surveyed 1,200 book club members across North America and found the following satisfaction ratings by group size:

3–5 members: 62% satisfaction rate
6–8 members: 78% satisfaction rate
8–12 members: 84% satisfaction rate (highest)
13–20 members: 67% satisfaction rate
20+ members: 51% satisfaction rate

The curve is clear: satisfaction rises sharply from very small groups, peaks in the 8–12 range, and declines as the group gets larger. The reasons for this pattern are rooted in communication dynamics.

Why 8–12 Works

At 8–12 active members, several things happen simultaneously:

Diverse perspectives without cacophony. Eight people bring eight different life experiences, reading habits, and interpretive lenses to a book. This diversity is what makes book club discussions richer than reading alone. Below eight, you lose diversity. A group of four friends who share similar backgrounds will converge on similar interpretations quickly, leaving little to discuss after the first 20 minutes.

Everyone can speak. In a 75-minute discussion with 10 people, each person has roughly 7.5 minutes of potential speaking time (accounting for the facilitator's role and natural pauses). That's enough for everyone to make substantive points without feeling rushed. Above 12–13 people, speaking time per person drops below 5 minutes, and quieter members begin to self-censor entirely.

Social loafing is minimized. Social loafing—the tendency for individuals to exert less effort in a group than they would alone—increases with group size. In a group of 5–10, your absence is noticed and your silence is conspicuous. In a group of 20, it's easy to sit quietly, mute your microphone, and mentally check out. Research from the European Journal of Social Psychology shows that individual contribution drops measurably when group size exceeds 12.

Subgroup formation is manageable. Groups larger than 12 naturally fracture into subgroups—cliques of 3–4 people who tend to talk among themselves. This fragmentation creates an uneven experience where some members feel like insiders and others feel peripheral. In groups of 8–12, the group is small enough to maintain a single conversational thread.

How Different Sizes Affect Your Club

3–5 Members: The Intimate Circle

Pros:

Deep, personal conversations. With only a few members, you can explore individual reactions in depth.
Easy scheduling. Finding a time that works for 4 people is exponentially easier than for 12.
Strong personal bonds. Members know each other well.
Low organizational overhead. Informal coordination works fine.

Cons:

One absence changes the dynamic dramatically. If your club has 4 members and 2 can't make it, you're having a one-on-one conversation, not a club meeting. A 2024 survey by Bookclubs.com found that clubs with fewer than 5 members cancel 38% of their scheduled meetings due to insufficient attendance.
Limited perspective diversity. You'll hear the same voices offering similar viewpoints, which can make discussions feel repetitive over time.
Groupthink risk. Small groups converge on opinions quickly, and members may hesitate to disagree when dissent is so visible.
Fragile to departures. If one member moves or loses interest, the club may collapse entirely.

Best for: Close friends who want a reading partnership more than a discussion group. Also works for specialized academic or professional reading groups where depth on a narrow topic matters more than breadth of perspective.

6–8 Members: The Small Group

Pros:

Still small enough for everyone to speak in every meeting.
Resilient to absences—losing 1–2 members per meeting still leaves a viable group.
Easy to manage informally; a shared group chat is often sufficient for coordination.
Good balance of familiarity and diversity.

Cons:

At the lower end (6), you're still vulnerable to cancellation if 3 members can't attend.
May lack the diversity of opinion that makes for truly surprising discussions.

Best for: Clubs that prioritize closeness and consistency over growth. Many long-running clubs (10+ years) have settled at this size naturally, having shed less committed members over time.

8–12 Members: The Optimal Range

Pros:

Highest satisfaction and retention rates according to available data.
Robust to absences—even with 3–4 missing, you have a strong core group.
Enough diversity for genuinely surprising interpretations and disagreements.
Large enough to sustain energy and momentum through temporary dips in engagement.

Cons:

Requires more intentional facilitation. A group of 10 won't self-moderate as naturally as a group of 5.
Scheduling becomes harder. Finding a time that works for 10+ people often means accepting that 2–3 will always be absent.
The facilitator role becomes more important—someone needs to ensure quiet members get airtime.

Best for: Most book clubs. This is the sweet spot where you get the benefits of diverse discussion without the downsides of large-group dynamics.

13–20 Members: The Large Group

Pros:

Attendance is rarely a problem—even with a 60% show rate, you'll have 8–12 at every meeting (which is, notably, the optimal number).
Greater diversity of age, background, and reading taste.
More social energy and event potential.
Losing a few members doesn't threaten the club's existence.

Cons:

Quieter members will disengage. In groups above 12, research shows that the top 3–4 most vocal members account for 60–70% of speaking time. The remaining members become an audience.
Subgroup formation creates in-group/out-group dynamics that can lead to cliques and uneven engagement.
Logistics are significantly more complex. You'll need dedicated tools for scheduling, RSVP tracking, and communication—a group text thread won't cut it. Platforms like Readfeed become essential at this size for managing the organizational overhead.
Book selection becomes contentious with more opinions and preferences to accommodate.

Best for: Community-oriented clubs that function as much as social organizations as reading groups. Library-sponsored clubs, church groups, and workplace clubs often land in this range. Consider using breakout groups of 4–5 for the discussion portion, then reconvening as a full group for final reactions.

20+ Members: The Community

Pros:

Functions as a community rather than a single conversation, which appeals to people who want belonging without the pressure of performing in a small group.
Enough scale for ambitious programming: author visits, panel discussions, multi-book tracks.
Self-sustaining—the community has enough inertia to survive leadership transitions and seasonal fluctuations.

Cons:

Not really a "discussion group" in the traditional sense. Full-group conversation with 20+ people is functionally a lecture or panel with audience questions.
Requires formal structure: a leadership team, communication protocols, defined roles.
High anonymity means members can drift without anyone noticing.
Book selection often defaults to popular, accessible titles because consensus is harder to reach.

Best for: Celebrity-led clubs, library programs, online communities, and clubs that have intentionally scaled into organizations. To maintain discussion quality, use a hub-and-spoke model: the community is the hub, and smaller breakout groups of 6–10 are the spokes where actual discussion happens.

The "Roster" vs. "Active Member" Distinction

One of the most important concepts in book club management is the difference between your roster (everyone who considers themselves a member) and your active membership (people who attend regularly).

Most clubs should expect active attendance to be 65–75% of their roster for in-person clubs and 55–65% for virtual clubs. This means:

To have 8 at a meeting, invite 11–12 (in-person) or 13–15 (virtual).
To have 10 at a meeting, invite 14–15 (in-person) or 16–18 (virtual).
To have 12 at a meeting, invite 17–18 (in-person) or 19–22 (virtual).

Track your club's specific attendance rate over 3–4 meetings and use that ratio to calibrate your roster size. Readfeed's RSVP and attendance tracking features make this data easy to collect and analyze over time.

When to Stop Accepting New Members

Establish a cap and communicate it clearly. "Our club has a maximum of 14 members. When a spot opens, we'll announce it in the group and on our Readfeed page." Having a cap creates several benefits:

Exclusivity drives commitment. Members who know their spot is valued treat it with more respect.
Discussion quality is protected. You never end up with a 22-person meeting that devolves into a lecture.
It forces intentional growth. Rather than saying yes to everyone, you can select members who complement the group's diversity.

When to Split a Book Club

If your club consistently has more than 14–15 people at meetings and discussion quality is suffering, it may be time to split. Signs that a split is overdue:

The same 4–5 people dominate every discussion while others stay silent.
Members express frustration about not getting to speak.
Side conversations break out during the main discussion.
Meetings consistently run over time because there are too many people to hear from.
New members stop attending after their first 2–3 meetings.

The most graceful way to split: keep the original club as-is and launch a second club as a "sibling" group. Let members choose which group they prefer, or split by reading preference (literary fiction vs. genre fiction, for example). Maintain a shared community space—a combined social event once per quarter, a shared book recommendations channel, or a joint year-end celebration.

Virtual vs. In-Person Size Considerations

Virtual clubs can run slightly larger than in-person clubs without sacrificing discussion quality, thanks to features like breakout rooms, muting, and hand-raising. A virtual meeting with 14 people, facilitated well, can work—whereas an in-person gathering of 14 in someone's living room feels crowded and chaotic.

However, virtual clubs also have higher no-show rates, so a larger roster is needed to achieve the same active attendance. A virtual club with 18 on the roster and 11 at a typical meeting may be functionally identical to an in-person club with 13 on the roster and 10 at a typical meeting.

The key metric isn't roster size—it's the number of people in the room (physical or virtual) when the discussion starts. Optimize for that number to fall between 8 and 12, and adjust your roster and recruitment accordingly.

Managing a Growing Club

If your club is organically growing beyond your ideal size, you have several options beyond splitting:

Waitlist model. Accept new members only when existing members leave. Maintain a waitlist and invite the next person when a spot opens.
Cohort enrollment. Open 3–5 new spots twice per year. This creates natural entry points and prevents constant disruption from new member onboarding.
Graduated structure. Create tiers: a "core" group of 10–12 who attend live discussions, and a broader community of readers who participate asynchronously through written discussion threads.
Multiple tracks. Run two books simultaneously—members choose which to read, and each track has its own discussion meeting with a smaller group.

Frequently Asked Questions

How many people should be in a book club?

The research-backed ideal is 8–12 active, regularly attending members. To achieve this, maintain a roster of 10–15 people to account for the 25–35% of members who will miss any given meeting. This range provides enough diversity of perspective for rich discussion while keeping the group small enough that every member has time and space to contribute meaningfully.

Is 4 people enough for a book club?

Four people can sustain a book club, but the group will be fragile. If one member can't attend, you're down to three—and if two are absent, the meeting is effectively cancelled. Clubs of four also tend to converge on similar opinions quickly, limiting discussion depth. If your group is four close friends who reliably attend, it can work well as an intimate reading partnership. For a more resilient and discussion-rich experience, aim to grow to at least 6–8 members.

What happens when a book club gets too big?

When a book club exceeds 14–15 regular attendees, discussion quality typically declines. The top 3–4 most vocal members dominate conversation, quieter members disengage, side conversations break out, and meetings run over time. The most effective solution is splitting into two sibling groups that maintain a shared community identity. Alternatively, use breakout rooms (for virtual clubs) or small-group discussion rounds (for in-person clubs) to create sub-conversations of 4–6 people before reconvening.

Should you limit book club membership?

Yes. Setting a clear membership cap—typically 12–15—protects discussion quality, creates healthy exclusivity that increases member commitment, and prevents the organizational overwhelm that comes with managing a large group. Communicate the cap openly, maintain a waitlist for interested readers, and open spots periodically when members naturally cycle out. A defined cap is one of the strongest predictors of long-term book club health.

What Size Should a Book Club Be? Finding the Right Number of Members