MacFreemium Chat & Messaging

Discord

Free

Free group voice, video, and text chat built for gaming communities — servers, screen sharing, and an optional paid Nitro tier for extra perks.

Chanty

Free (up to 5 team members, 20GB team storage); Business from $3/user/mo billed annually ($4/user/mo billed monthly); Enterprise is custom pricing

Team chat with unlimited message history and a built-in task manager — free for small teams, from $3/user/mo for the rest.

Twist

Free forever (1 month of message history, up to 500 members, 5GB storage); Unlimited plan $6/user/mo for full history and unlimited storage

Thread-based team chat from the makers of Todoist, built to replace always-on chat with asynchronous, on-topic conversations — free forever, or $6/user/mo for full history.

Zulip

Free (Zulip Cloud: 10,000 messages of history, 5GB storage; self-hosted: every feature, unlimited history, no cost); paid Cloud and self-hosted tiers exist but list no public per-seat price on the official pricing page

Open-source, thread-based team chat — free to self-host with every feature included, or a managed Zulip Cloud plan with a real free tier.

Mattermost

Free limited-use evaluation edition (“Mattermost Entry”) for self-hosting; Professional, Enterprise, and Enterprise Advanced plans are all “contact sales” — no public per-seat price listed on the official pricing page

Open-source, self-hosted team chat — Homebrew’s own listing calls it exactly that: a “Slack-alternative.”

Microsoft Teams

Free (personal, 1 user); Microsoft Teams Essentials from $4/user/mo billed yearly; bundled into Microsoft 365 Business Basic from $7/user/mo

The largest team-chat platform by market share, with a native Mac client — free for personal use, business plans from $4/user/mo.