Slack is very good software. That's the awkward starting point of every “Slack alternative” page, and pretending otherwise just wastes your time. The reason people leave isn't that the product is bad — it's that the free plan hides your history after 90 days, the paid plan bills per person per month forever, and the admin features you eventually need live one tier further up.
Fluid Chat is the same daily workflow with none of those three properties. Here's the full accounting, including the parts where Slack wins.
The three reasons teams actually switch
- 1The 90-day wall. Slack's free plan gives access to roughly the last 90 days of messages and files. Older content isn't deleted — it's retained and inaccessible, which is somehow more irritating. Search stops reaching, onboarding gets worse, and decisions get relitigated.
- 2Per-seat billing. The cost of your chat tool grows with your headcount, forever, whether or not usage grows with it. Hiring becomes a line item in a budget it has nothing to do with.
- 3Tiered governance. Audit logs, guest accounts, retention policies and data export are the features a company needs at exactly the moment it can least justify a tier upgrade.
Row by row
| Fluid Chat | Slack Free | Slack paid | |
|---|---|---|---|
| Message history | Unlimited | Last ~90 days | Unlimited |
| Cost per person | $0 | $0 | Monthly, per seat |
| Where your data lives | Your server, or ours | Their cloud | Their cloud |
| Source code | All of it, open | Closed | Closed |
| Channels, DMs, group DMs | Yes | Yes | Yes |
| Threads and reactions | Yes | Yes | Yes |
| Search operators | Yes, over all history | Yes, within the window | Yes |
| Guest accounts | Included | No | Yes |
| Audit log | Included | No | Higher tiers |
| Retention policies | Included | No | Yes |
| Full data export | Included | Limited | Yes |
| Incoming webhooks | Yes | Yes | Yes |
| Huddles, voice and video | No | Yes | Yes |
| Native mobile apps | Responsive web | Yes | Yes |
| Slack Connect | No | Limited | Yes |
| App directory | No (open API instead) | Yes | Yes |
| SSO / SAML | No | No | Yes |
Slack plan details are summarised from Slack's published plans and can change — check slack.com/pricing for current terms. Slack is a trademark of Salesforce, Inc. Fluid Chat is an independent project and is not affiliated with or endorsed by them.
What Slack does better
Four rows in that table are losses, and they're not small ones:
- Huddles, voice and video. Slack's huddles are excellent and Fluid has nothing equivalent. If your team's default for “this needs five minutes of talking” is a huddle, that's a real cost to switching.
- Native mobile apps. Fluid's web client uses a drawer layout and is genuinely usable on a phone, but a web client and a native app are not the same thing, particularly for push notifications.
- Slack Connect. Talking to other companies' workspaces is a genuine network effect, and network effects can't be cloned by a competitor.
- The app directory. Thousands of prebuilt integrations. Fluid has an open, documented API with a generated OpenAPI 3.1 spec — better if you're building, worse if you wanted to click Install.
There's a fifth, softer one: nobody has ever needed to be trained on Slack. Switching a team is a change-management exercise, not just a migration.
The migration honesty section
There is no Slack importer yet. This is the biggest practical obstacle to moving and it would be dishonest to bury it under a feature table.
What Fluid does have is a clean way out of itself: full data export as JSONL, CSV and a file manifest, on the free plan. So the asymmetry is real — leaving Fluid is solved, arriving from Slack isn't. Most teams handle it by running Slack's own export for the archive, starting fresh in Fluid, and keeping the old export as a searchable file. Writing a proper importer is an excellent first contribution if this is blocking you.
The same workday, a different bill
For the parts of the day that are actually chat, the two products are close enough that most people stop noticing within a week:
- Public and private channels, a channel browser, archiving, DMs and group DMs up to nine people.
- Threads with reply counts, participant facepiles and the “also send to channel” escape hatch.
- Mentions including
@here,@channel,@everyone, user groups and channel links. - Emoji reactions with a full picker, skin tones and workspace custom emoji.
- Quick switcher on
⌘K, full keyboard shortcuts on⌘/,↑to edit your last message. - Unread counts, a “new messages” divider, mark-unread from any message, activity feed, saved items and reminders.
- Search with
in:,from:,has:,is:pinnedand date operators — over your whole history rather than a rolling window.
Try it for an afternoon with one channel.
The lowest-risk evaluation is to move a single team's standup into a free Fluid workspace for a week and see whether anyone misses anything. Costs nothing but the afternoon.
Should you switch?
A short decision rule, since that's what you actually came for:
- 1If you need huddles, SSO or Slack Connect — stay on Slack. Nothing here changes that.
- 2If you're on Slack Free and the 90-day limit is biting — switch. That's the cleanest case, because you're comparing against $0 and losing nothing but the app directory.
- 3If you're on a paid plan for history and admin features — do the maths at your headcount. Those features are free here, and the invoice isn't a rounding error at 50 people.
- 4If data residency or self-hosting is a requirement — Slack can't do it and Fluid can. That's not a comparison, it's a filter.