Guide
What Slack actually costs a community
The short answer: at Slack Pro’s published $7.25 per user per month (billed annually), a 20-person club is $1,740 a year, a 100-person association is $8,700, and a 500-member community is over $43,500 — which is why essentially every community Slack you’ve ever joined runs on the free plan and quietly loses its own history.
The table
| Members | Per month | Per year |
|---|---|---|
| 15 | $108.75 | $1,305 |
| 20 | $145 | $1,740 |
| 50 | $362.50 | $4,350 |
| 100 | $725 | $8,700 |
| 250 | $1,812.50 | $21,750 |
| 500 | $3,625 | $43,500 |
One prospective community organizer did exactly this math on Reddit — 500 recruiters at $7.25 a head — hit the $3,600-a-month line, and asked the obvious question: how does anyone run a community on this? The honest answers from people running them: they don’t. They use the free plan, negotiate special pricing, or were grandfathered years ago.
What “free plan” really means
Slack’s free tier hides messages and files older than 90 days, and Slack has stated that free-workspace data older than a year is deleted. For a company trial that’s a nudge to upgrade. For a community it’s structural amnesia: the answer to every recurring question, the decision from last spring, the onboarding thread you point newcomers at — gone on a rolling schedule. Communities are long-memory organisms; the free plan is a short-memory product.
Why per-seat pricing can’t fit groups
Per-seat pricing assumes each seat produces revenue — true of employees, false of members. A community’s members are its cost under this model: every new person the group succeeds in attracting raises the bill. The incentive lands on the organizer as a tax on growth, which is the one thing a community is for. This isn’t Slack being greedy; it’s workplace pricing applied to a non-workplace shape. Slack’s nonprofit discounts (worth asking about) soften the slope without changing it.
The alternatives, mapped
Stay free and accept amnesia — legitimate for pure-chat communities that don’t keep records. Discord — free with unlimited history; the trade is server complexity and a register many non-gaming groups can’t use. Flat per-group pricing — the shape that matches how groups actually work: one price for the hub, growth free. That’s TinyHubs’ entire pricing model — $199 a year covers a 50-person group, $399 covers any size, and inviting member 51 costs nothing.