Slack sits firmly at the top of the online communication platform pile. The instant messaging cum team collaboration workspace has millions of users from businesses and organizations of all sizes. Slack's success is built upon a simple idea---life is all about communication, and email is no longer suitable for fast-paced working environments.

That's not to say there isn't a place for email. But email threads become disjointed, tangled messes with multiple respondents. Why waste time when there is a better option available?

1. Rocket Chat

Rocket Chat is an open-source Slack alternative. This means the chat client is completely customizable if your programming skills are up to scratch. Rocket Chat is a resolute experience out-of-the-box. It offers many features that free and paid Slack versions don't have:

  • Audio and video conferences.
  • Integrated live-chat for websites.
  • Screen sharing.
  • Theming, branding, and white label installation packages.

Rocket Chat has an intuitive UI, which further exemplifies the easy experience on this chat platform.

Download: Rocket Chat for Windows | macOS | Linux | Android | iOS

2. Microsoft Teams

For a long time, Microsoft Teams was only available to Office 365 subscribers. But Microsoft changed that and now you and can use Microsoft Teams for free. There are some limitations, understandably. But the free version of Microsoft Teams packs a heap of useful features into its free offering.

One of the standout features for Microsoft Teams is unlimited messaging. Where free Slack limits your team to 10,000 messages, Microsoft Teams lets you go wild. Another plus point is the extensive list of Microsoft Teams integrations, of which you can add over 140 to your free subscription.

One slight downside to Microsoft Teams is the slightly confusing sign-up and sign-in process. Here's what happened when I tried to create a Microsoft Team with a friend for the MakeUseOf Microsoft Teams vs. Slack comparison:

Microsoft makes accessing Teams a difficult enough procedure that two other friends invited to test Teams with me gave up. Their pre-existing Microsoft accounts couldn't use any of the Get link to team links sent from within the Teams app to gain access. Thinking the issue could relate to their organization email accounts (accounts created by their workplace), they switched to personal accounts, but still had the same issue.

Sign-up irritations aside, Microsoft Teams is a great free chat tool.

Download: Microsoft Teams for Windows (64-bit) | Windows (32-bit) | macOS | Android | iOS

3. Zulip

Zulip is "The world's most productive team chat." I'm not sure if that claim is verifiable. However, I will say that Zulip is an open-source messaging tool that a lot its competitors could learn a thing or two from.

Zulip does several things right. A clean and intuitive UI, extra functionality including markdown, inline images and videos, excellent security credentials, and heaps of integrations for productivity and more.

Another Zulip feature I really like is the nested topics. For example, you subscribe to a Zulip Stream (which is like a Slack channel). Then, within the Stream, there are individual topic threads. It helps to keep the Zulip chat clean, and your team productive.

Download: Zulip for Windows | macOS | Linux | Android | iOS

4. Bitrix24

Bitrix24 is a fantastic Slack alternative for a small team looking to integrate project management into their client chat. Often cited as one of the best free project management tools, Bitrix24 also features several premium Slack components.

Bitrix24 has integrations for social media, task and project management, document management, team calendars, email, and more. Furthermore, Bitrix24 provides a well-received free CRM platform. What a package!

Download: Bitrix24 for Windows | macOS | Android | iOS

5. Chanty

Chanty is a handy free Slack alternative for slightly smaller teams. The free version of Chanty allows up to 10 team members, with ten integrations. If this sounds like it would suit your team, add in that Chanty allows unlimited public and private chat, has a searchable history, integrated productivity tools, and up to 20GB storage for your team.

Overall, Chanty offers a neat little instant messaging package, combining several premium Slack features into their free offering.

Download: Chanty for Windows | macOS | Debian | Fedora | Android | iOS

6. Fleep

Fleep! Sorry, it just sounds good. Go ahead: say it out loud.

Now that is taken care of, I can introduce you to a messaging client with a focus on team integration. Fleep does something differently to Slack. While Slack is excellent for chatting with a single team at a time, Fleep lets you reach out and chat with other people and organizations without leaving the client.

Furthermore, it brings those stubborn, email wielding individuals into the fore. So long as you have an email address, Fleep will bring the conversation to you.

Download: Fleep for Windows | macOS | Android | iOS | Linux (installation instructions, not installer)

7. Mattermost

The list of the best free Slack alternatives winds-up with open source Mattermost.

Mattermost is a self-host option. If you host Mattermost on your server, you can use its features for free. It is a secure option which supports end-to-end encryption too. Plus, it has over 400 integrations you can add, without limit. In that, you can tool Mattermost up to suit the requirements of your team, rather than an out-of-box alternative.

Download: Mattermost Desktop for Windows (64-bit) | Windows (32-bit) | macOS | Linux | Android | iOS

Download: Mattermost Server for Linux or Docker

What Is the Best Free Slack Alternative?

Slack is excellent. It is. I use it for work. My friends and I have a private team. There are loads of specific interest Slack teams you can join, too. You can organize Slack to get the most out of it.

That doesn't mean you shouldn't shop around for an alternative. The free Slack alternatives on this list will provide everything your team needs. In some cases, you'll get more features than you expect from a free service.

Consider your requirements and check if your free Slack subscription is pulling its weight. Is it time to find a new workhorse? Alternatively, do you need to boost your existing Slack productivity and get more out of it? Here are some clever Slack bots you can install to give your team a productivity push!

Have you joined the remote work force? Our working from home resources can help you get set up and stay organized.