What is the difference between Slack and Flock?

Slack is best for Teams that need organized, searchable communication, while Flock is best for Teams wanting messaging with built-in productivity tools. Slack starts at $7.25/user/mo and Flock starts at Free.

Is Slack or Flock cheaper?

Slack starts at $7.25/user/mo with a free tier. Flock starts at Free with a free tier.

Is there a free alternative to Flock?

Both Slack and Flock offer free tiers.

Slack vs Flock

Slack is team messaging platform with channels, threads, and integrations for workplace communication, while Flock is team messaging with built-in to-dos, polls, notes, and file sharing. The biggest difference up front: Flock is free, while Slack starts at $7.25/user/mo. Slack is built for teams that need organized, searchable communication, whereas Flock targets teams wanting messaging with built-in productivity tools.

At a glance

	Slack	Flock
Best for	Teams that need organized, searchable communication	Teams wanting messaging with built-in productivity tools
Starting price	$7.25/user/mo	Free
Free tier	✓	✓
Open source	—	—
Free tier available	✓	✓
Open source	—	—
Channels	✓	—
File Sharing	✓	—
Huddles	✓	—
Integrations	✓	—
Notes	—	✓
Polls	—	✓
Threads	✓	—
To-Dos	—	✓
Video Calls	—	✓

Slack

Strengths

Massive integration ecosystem with 2,400+ apps
Excellent search across all messages and files
Familiar interface that most people already know
Strong API for custom bots and workflows

Weaknesses

Expensive at scale — costs add up fast with large teams
Can become noisy and distracting with many channels
Free tier limits message history to 90 days
Desktop app is resource-heavy

Try Slack → Full review

Flock

Strengths

Lightweight to-do lists keep daily tasks front and center without project-management overhead
Includes Polls as a core feature, purpose-built for team communication workflows
Free for up to 20 users — generous enough for most small teams to get real work done
Established product with 12+ years on the market and a mature ecosystem

Weaknesses

Free plan exists but key features are locked behind the paid upgrade
Fewer built-in features means you may need additional tools to cover gaps
Notification overload is a real problem as the number of channels grows
Limited team/admin features if your organization eventually scales up

Try Flock → Full review

The bottom line

Pricing: Flock is completely free (Free for up to 20 users), which makes it the obvious pick if budget is the top concern. Slack starts at $7.25/user/mo, but Free for small teams, 90-day history. That cost buys you a more polished or feature-rich experience, so it comes down to whether the extras justify the spend.

Feature gaps: Slack offers Channels, File Sharing and Huddles that Flock lacks. Flock brings Notes, Polls and To-Dos that Slack does not have.

Team fit: Slack is geared toward any size teams, while Flock is aimed at small teams teams. Pick the one that matches where your team is today and where it is headed — migrating tools later is always painful.

Where each tool shines: Slack's biggest strengths are: massive integration ecosystem with 2,400+ apps. excellent search across all messages and files. Flock's biggest strengths are: lightweight to-do lists keep daily tasks front and center without project-management overhead. includes polls as a core feature, purpose-built for team communication workflows.

Watch out for: With Slack, users commonly note that expensive at scale — costs add up fast with large teams. With Flock, the main complaint is that free plan exists but key features are locked behind the paid upgrade.

Choose Slack if...

Your profile matches its sweet spot: teams that need organized, searchable communication
You specifically need Channels and File Sharing
You care about excellent search across all messages and files
Your team size fits the any size profile Slack is designed for
The free tier works for you: free for small teams, 90-day history

Choose Flock if...

Your profile matches its sweet spot: teams wanting messaging with built-in productivity tools
Budget is a hard constraint — Flock is free, Slack is not
You specifically need Notes and Polls
You care about includes polls as a core feature, purpose-built for team communication workflows
Your team size fits the small teams profile Flock is designed for