The short answer
- Already paying for Google Workspace or Microsoft 365? Chat and meetings are included, so a separate Slack Pro seat at $8.75/user/mo may be a duplicate: modeled first-year saving $80 per seat. the math
- Slack Free keeps 90 days of message history, 1:1 huddles only and up to 10 apps, and deletes data older than a year. slack.com
- Self-hosting Mattermost is modeled to cost $1,355 more than Slack in year one for a single seat once upkeep counts; it only pays with a larger team. the math
- Stay on Slack if Slack Connect channels with customers, Workflow Builder or years of searchable history matter to you. slack.com
Who should switch, and who shouldn't
Switch if
- You already pay for Google Workspace or Microsoft 365 for email and documents: Chat and Meet, or Teams, come with them. the math
- Your team is small, 90 days of searchable history is enough, and huddles are mostly 1:1. slack.com
- You have someone who already runs servers and a team big enough that per-seat fees add up: Mattermost is free to self-host. the math
What Slack costs today
List prices from the vendor's pricing page, as stored in the Stackcut catalog. Each price links its source.
| Plan | Billed monthly | Billed yearly (per month) | What you get |
|---|---|---|---|
| Slack Pro | $8.75/user/mo | $7.25/user/mo | Unlimited message history and apps; group huddles (up to 50 people, 25 on video); group Slack Connect |
| Slack Business+ | $18/user/mo | $15/user/mo | Everything in Pro plus advanced AI, SAML SSO, SCIM; huddles up to 50 people |
The alternatives, ranked
4 ways out, ranked by modeled saving in the first year after setup and upkeep (4 priced). Modeled, not measured: each figure links the math on the recipe page.
- Paths are modeled per seat against Slack Pro at $8.75/user/mo. The Workspace and Microsoft 365 paths assume you already pay for those suites. recipe
What team chat costs at 1, 5 and 20 users
Every paid option here is per user. The suites include email, storage and documents, so compare them only if you'd buy them anyway.
| Option | List price | 1 user | 5 users | 20 users |
|---|---|---|---|---|
| Slack Pro today | $8.75/user/mobilled monthly | $8.75 | $43.75 | $175 |
| Slack Business+ today | $18/user/mobilled monthly | $18 | $90 | $360 |
| Slack Free90 days of history | $0free plan | $0free tier | $0free tier | $0free tier |
| Google Workspace Business Starterincludes Chat and Meet | $8.40/user/mobilled monthly | $8.40 | $42 | $168 |
| Microsoft 365 Business Basicincludes Teams | $7/user/mobilled yearly | $7 | $35 | $140 |
| Mattermost (self-hosted) | $0 licenseAGPL-3.0 source, MIT for its builds | $0+ your server | $0+ your server | $0+ your server |
How to leave Slack
Export first, then cancel. Every step links the vendor's own help page, checked on the date shown.
How to leave Slack
Export first
- Public channels (messages and file links): Admin → Workspace settings → Security → Import & export data → Export (ZIP of JSON). Free and Pro export public channels only; private channels and DMs need Business+ or Enterprise. On Free, file links cover the last 90 days. slack.com
What you lose
- Canvases and Lists turn read-only
- Existing Workflow Builder workflows stop working
- Guest accounts are deactivated and Slack Connect channels disconnect
- Everyone is removed from user groups
Cancel
- Export what you need first (see export).
- Admin → Manage billing → Overview → Change plan details → Downgrade to Free.
- Workspace Owners, or the member who upgraded the workspace, can do this.
- Takes effect
- You choose: right away or on your next renewal date.
- Refunds
- Not stated for a downgrade to Free. Slack credits unused paid time only when you move from Business+ to Pro.
- After you cancel
- Free shows the most recent 90 days of messages and files, deletes data older than 1 year, allows 1:1 huddles only and up to 10 apps.
Not covered by the paths above, per the recipe: App integrations, Slack Connect (external), Workflows, Slack AI. If you rely on one of these, keep the incumbent or check the path closely.
Open-source and forkable options
- Mattermost: Free self-hosted team chat with full history. License: AGPL-3.0 source (MIT for Mattermost's own builds) · source code
Open source means no license fee, not free to run: the server, backups and upgrades are yours. Read the license before you fork or resell; several of these are open-core or source-available.
FAQ
What do I lose if I downgrade Slack to Free?
History beyond 90 days (and data older than a year is deleted), group huddles, more than 10 apps, Slack Connect channels, guests, working Workflow Builder workflows, and editable Canvases and Lists. slack.com
Can I export private channels and DMs?
Not on Free or Pro: those plans export public channels only. Private channels and DMs need Business+ (after applying for the self-serve export tool) or Enterprise. slack.com
Do I get money back if I downgrade mid-cycle?
Slack's help page doesn't state a refund for moving to Free. You can choose to downgrade on your next renewal date instead of right away. slack.com
Keep reading
Check your own stack
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Or ask your agent
Connect the Stackcut MCP server (https://stackcut.io/mcp, no API key) and ask: “We're 5 people on Slack Pro and also pay for Google Workspace. Do we need both?”
find_alternatives({"vendor": "Slack", "seats": 5,
"features_used": ["Channels and DMs", "Huddles (calls)"]})