Slack vs Microsoft Teams: Business messaging apps battle it out

If you work in an office, chances are you're using, or have used, either Slack or Microsoft Teams. Corporate communication platforms that were meant to take us off email, but have, instead, become apps we use in tandem with legacy messaging.

Both have their unique features, but essentially they're made up of instant messaging channels, video calling, emojis, and AI... lots and lots of AI. New features and capabilities are added each year, but really the main purpose is to act as a collaborative hub for your teams.

Slack vs. Microsoft Teams: Chat

We'll start with the main reason for having either Slack or Microsoft Teams: Chat. It's the first thing you'll see when you log in and the simplest function on either platform. Chat 'Channels' sit in sidebars, with all the available participants within your organization. In some cases, outside parties can also reside in this space; we will get to that later on in the review.

You can be a part of multiple work groups, and switch back and forth between them. You can send direct messages to a colleague or group team members together for chats. You can also create threads within those chats to stay on a particular talking point.

Neither platform is just text-based, however, as you can also share files, linked external resources, and even embed data through integrated third-party applications. You also have tools to signal location, working hours, specific tasks, and job roles. For instance, on Slack you can see the time for colleagues in other countries, or use an emoji to let people see you're in a meeting.

All these internal chats can grow quite quickly and leave you with endless scrolls. But both Teams and Slack have search functions that can pull out specific conversations within channels. And some of their AI functions can recall conversations you may have missed.

One of the main differences between the two platforms, however, is that Slack has Canvas, while Teams has a Whiteboard. Canvas is a place to store assets or relevant data for a particular conversation – it can stand alone or be attached to a chat/channel. Whiteboards are a little different in that while colleagues can collaborate on a single board, they can, as the name suggests, write directly onto it.

As far as chat goes, Teams and Slack are quite evenly matched. This is the one area that they undisputedly do very well. Though there isn't anything to really separate them.

Slack vs. Microsoft Teams: Calling and screen sharing

Initially, video calling only really made sense on Slack, because Teams is part of the wider Microsoft 365 suite -- there was another app for it. However, since the pandemic, Teams has become the de facto video calling app for Microsoft users, while Slack has quietly added that functionality.

Slack uses a function called "Huddles," which starts as a voice-only meeting. Participants can enable cameras and even expand the Huddle window as they go along. It's really easy to launch, and you can also continue your text-based conversation within the channel. There's also some jaunty hold music while you wait for your guests to accept.

For paid plans, you can have up to 50 participants on a paid plan, but only two if you're using the free tier. And anything shared while on the call – messages, links, documents – will be saved for future reference.

If you want more participants while on the free tier, then Teams is the clear winner here as it allows for 100 participants for a maximum of 60 minutes.

Calls can be initiated from within a chat or by typing /calling in the command box at the top of the window. You can share your whole screen when in a meeting or if you're giving a presentation, use PowerPoint Live, which displays your deck to other participants but shows you the presenter view that you'd work with if you were giving the presentation while connected to an external display. This way, you can see your upcoming slides and, perhaps more importantly, your presenter notes.

It's possible to place calls to people not in your workspace through direct dialing. In Teams, this feature is built-in but must be enabled at the organization level. In Slack, it's achieved through the use of integrations.

We feel Teams has the edge here. The free tier lets you make calls with larger groups of people and PowerPoint Live brings the best features of in-point presenting to the digital realm.

Slack vs. Microsoft Teams: Integrating applications

Both Slack and Teams have the potential to sit at the heart of your organization's workflow. That's because they each integrate with third-party applications to significantly extend the base offering. Integrating third-party tools reduces the need to switch between applications, helping team members stay focused.

You can integrate up to 10 applications on Slack's free tier, and an unlimited number if you're on a paid subscription. There are more than 2600 to choose from in the Slack App Directory, you can build your own workflows, and there's an API to craft custom apps specific to your organization. Slack claims that more than 650,000 customized apps are used on its platform every week.

Teams is linked to Microsoft AppSource, which includes more than 2100 add-ons (for Teams specifically) at the time of writing. Although this is slimmer picking than Slack offers, it does include business essentials, like Trello, RingCentral, Lucidchart, and Salesforce, the latter of which owns Slack. Organizations with the necessary skills can also produce their own apps – or contract out if they don't have the talent in-house.

On numbers alone, Slack wins here, with almost 20% more apps in its associated store. Two surprising absentees from AppSource are Teams connections to Dropbox and Google Drive, which do appear in the Slack App Directory. If the two are still evenly matched on your own tick-list, go through each store and check whether the apps on which you rely are included.

Slack vs. Microsoft Teams: Platforms and apps

Both services are available on a wide range of platforms. Teams has apps for Android, iOS, Windows, and macOS, although its Linux application disappeared in 2022. Slack continues to support Linux with a dedicated app, alongside Windows, macOS, iOS, and Android, although as of March 2002, it no longer supports Fedora Linux distributions. We find this surprising as Red Hat Enterprise Linux, which is one of the two named distros it does support (the other being Ubuntu LTS) draws code from the Fedora Project.

Recognizing that business frequently takes place in the browser, they're both available as web versions. This is a handy workaround for users of either service who are tied to a Chromebook, as well as for Linux-based Teams users.

Browser support, while good, isn't complete in either case. Teams don't support audio and video calling or screen sharing in Firefox (bad news again for Linux users for many of whom Firefox is the default browser), or to degrees in various releases of Safari on macOS.

Slack huddles (calls) are officially only supported on Firefox and Chrome, which could be bad news for Edge and Safari users if taken literally, although we did manage to run a huddle in Opera which, although Chromium-based, isn't Chrome in the truest sense of the word.

Slack has the edge here, as its Linux client opens it up to a wider range of platforms. However, as Linux still only claims about 3% of the desktop market, there's very little to separate the two. Unless you're a Linux user, platform support is unlikely to greatly influence your decision.

Slack vs. Microsoft Teams: AI

Over the last two years, both platforms have become AI playgrounds, with many new features (for better or worse) shoved into every conceivable space. Slack AI is a very bloated platform, but it does provide a number of useful shortcuts for catching up on chats, summarising threads, and also answering natural language questions.

Microsoft has integrated Copilot into Teams. Again, you can ask it to draw out specific information from chats, which can help colleagues spread across time zones catch up with interactions they missed when they weren't working. It performs a similar trick in meetings with transcription enabled, and for late joiners, there's an option to see a summary of what's been missed. You can ask it where participants agree or disagree on a topic, which could be a neat way of rounding out a meeting and providing discussion points for the next agenda.

Slack vs. Microsoft Teams: Price

Teams has a significant advantage here, in that it sits within an ecosystem of complementary products.

Slack still sells itself as a stand-alone service, though it's also a part of Salesforce now so it has plenty of benefits that way. Teams is available as part of Microsoft 365, which will inevitably make it a tempting proposition for existing users.

Slack's paid plans start at £7 per active user, per month (and active means just that: Slack will monitor usage and rebate you pro-rata for any team members who aren't using your workspace). With a paid plan you can integrate an unlimited number of third-party apps, get access to the workflow builder, make calls between up to 50 users, implement OAuth sign-in with Google, and control how data is retained (but not necessarily where, as you need to upgrade to Business+ for data residency controls). You also get round-the-clock support.

Teams Essentials is a little over half the price of Slack's entry-level tier. For £3.10 per user per month, you get unlimited group meetings of up to 30 hours per session, with up to 300 participants apiece; unlimited chat with co-workers and customers; live captions in meetings, so long as you're using English; Microsoft Whiteboard integration, plus integration with collaborative apps; meeting transcripts; and access to the web versions of Word, Excel, and PowerPoint.

Teams looks like the more enticing deal overall, particularly if your business already subscribes to Microsoft 365.

Note that neither of these entry-level paid plans includes an uptime guarantee. If that's an important consideration, you'll need to sign up for Teams Basic, at £5.40 per user per month, or Slack Business+, at £7.20 per active user per month.

Slack vs Microsoft Teams

Slack and Teams are formidable collaboration platforms, that facilitate both remote and side-by-side working by consolidating what were once discrete functions – messaging, file sharing, calling, and more – into a single interface. Use either and staff will spend less time switching between apps while, behind the scenes, the administrative burden is reduced as admins can contract to a single supplier with everything residing in the cloud.

In truth, there's little to choose between them, although by breaking them down, differences do start to appear. For businesses in which some staff use Linux, Slack is the more tempting proposition, even if the majority of the workforce is tied to Windows or macOS.

However, for organizations already signed up to Microsoft 365, Teams looks like better value, it has the edge where the free offerings are concerned and, if you're not yet tied to either platform but willing to take out a paid sub, it does appear to offer more for your money there, too. Ultimately, that pushes it ahead, but with each platform continuing to innovate and AI becoming increasingly important in UCaaS, we'll be keeping an eye on both to see what happens next.