Rocket.Chat: A Self-Hosted Slack Alternative
Slack's free tier caps message history at 90 days, which is what actually pushes most small teams to a paid plan. The savings here are more modest than most of what's on this site — worth saying upfront.
I want to set expectations before the numbers: this isn't one of the dramatic-savings posts on this site. Slack Pro is $7.25/user/month (annual billing), and for a small team that's not a huge number per seat. What actually pushes teams to pay is Slack's free-tier 90-day message history limit — lose access to anything older than that, and paying starts looking necessary rather than optional.
The actual numbers
| Slack Pro | Self-hosted Rocket.Chat | |
|---|---|---|
| 5-person team | $36.25/month (5 × $7.25) | $24.00/month (dedicated VPS) |
That's about a 34% reduction — real, but more modest than most swaps on this site. If your team is under 10 people and Slack Pro's price doesn't bother you, I wouldn't force this migration on cost alone. The stronger reasons to self-host chat are unlimited message history and not having a third party able to see or export your team's conversations, not the monthly bill.
What it takes to run
Rocket.Chat is a full-featured team chat platform — channels, DMs, threads, file sharing, and reasonably close feature parity with Slack. It's built on Node.js with MongoDB, and it's another one of the heavier tools on this site: 1.5GB RAM idle, climbing to 3–4GB under real use with 50+ active users. A 2GB box will technically run it but gets sluggish under any real load, so I'd budget the same $24/month, 4GB Vultr tier I use for Chatwoot rather than trying to squeeze it onto a lighter shared instance.
One specific gotcha worth knowing before you start: recent Rocket.Chat versions require MongoDB to run as a replica set, even for a single-server deployment — that's a MongoDB feature Rocket.Chat depends on for real-time updates, not optional configuration. It's a documented step, but it's an extra one compared to a normal single-instance database setup, and skipping it will break things in ways that aren't obvious from the error messages.
Where Slack still wins
Slack's app/integration marketplace is enormous and mature — if your team relies on a dozen third-party Slack integrations, Rocket.Chat's ecosystem is smaller and you should check your specific integrations exist before committing. For a team that mainly wants channels, DMs, and full control of its own message history, this is a reasonable swap with modest but real savings.
I run mine on a dedicated Vultr instance, the same tier as Chatwoot — see the full cost roll-up for how the pieces fit together.
Disclosure: this post contains an affiliate link to Vultr. If you sign up through it, I may earn a commission at no extra cost to you. I only link to providers I actually use.