Collaboration software is present almost in every business, in one form or another. The one that first comes to mind and was in many ways a precursor of the field – Slack – has found more and more capable rivals with every passing year. However, now in 2020, Teams by Microsoft seems like it will lead the pack for a while.

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    So, what are the long-term prospects of both Slack and Teams? Will Teams keep chipping away at the yesterday's leader?

    One of those – Teams – has, in my opinion, slowly taken the lead as the top software in its category, and businesses around the world have noticed. Because of the global spike in remote work due to pandemic, thousands of organizations had to move at least part of their operations online.

    Microsoft reported a huge user base spike – from 32 to 44 million daily active users in just seven days in March. Slack, feeling the heat, has stopped revealing this metric a while ago, which peaked at 12 million in October 2019. This, however, does not mean the fight is over, as Slack has proudly reported more than 12.5 million concurrent sessions in some days in March.

    slack vs teams trends

    The graph from Google Trends shown above pictures how Teams (red line) had a massive growth of relative interest in comparison to its competitor (Slack is the blue line) in early 2020.

    How are Slack and Teams different?

    Slack CEO does not believe them to be direct competitors, and believes Microsoft has an “unhealthy obsession” with killing Slack. He says MS is afraid Slack damages the foundation of the Office empire.

    Many think differently, and see Slack as a direct competitor as well. While the programs offer various extra features, at their core both Slack and Teams are catalysts of organizational efficiency and communication. They do not even go about it in really different ways! But let’s try to focus on key differences anyway.


    Looking at bare-bones version of both programs (that is, without integrations), reveals quite a lot already.

    While Slack’s chat looks much better, in the corporate world having separate emails for all channels, as Teams do, can be useful. Teams also has a nicer built-in gif sharing.

    A key drawback for some is the messages and storage limitation of the free Slack version – which limits the workspace to 10000 messages total, and the rest... Well it is unavailable. Teams has no such limit. In terms of storage, Slack offers 5GB per team in the free version, and paid tiers offer 10 and 20GB respectively. Free Teams, meanwhile, offers 2GB per user and 10 per team, and a strong 1TB in paid versions.

    Another advantage Teams has in terms of collaboration is its more capable videoconferencing. Slack until recently gave free users only 1v1 conversations and videocalls, while Teams starts with 250 for its free users. It also has screen recording and screen sharing in its free option. Finally, Teams has some perks for companies that look for scheduling and shift management software, as it has those features.


    Slack and Teams have a different approach to integrations – Slack offers a vast library of third-party integrations but has a rather annoying limit of 10 for the free version. Only the paid option unlocks the full potential of its over 800-strong extensions base.

    On the other hand, Teams has something much more powerful – you get the entire Office 365 package. Slack has no real competing option here. Other than that, MS Teams has only about 200 integrations as of today – but there is no limit on how many can be installed at once in either paid or free plans. In my opinion though, the way Teams organizes integrations with tabs is pretty neat and allows apps to be accessed easier.

    One side note – Teams also has a native calendar and email integration, which is a big plus. Slack integrations are also mostly related to messaging and are in chat window only. Tabs in Teams open up a whole new array of options.

    Interface and ease of use

    For millions, Slack has paved the way in how collaboration apps should work and look like – and this is one of the areas where in my opinion, Teams still feels heavier and less intuitive. Slack fans rightfully say that it can practically be used without any learning curve, while Teams is noticeably more complex.

    Slack has promised to roll out new features, such as the convenient compose option (accessible from anywhere), to make it even more user-friendly and organized. Its latest redesign, which arrived in March, gave users a new sidebar and noticeable improvement where it was lacking before – the search function.

    Teams, on the other hand, struggles a bit with its UX, especially with how it presents the chat messages. MS engineering team is aware of this issue and says it is looking to correct it in the next redesign. The desktop app is a bit clunky and customization options are scarce. Fortunately, this is one of the rare drawbacks Teams has.


    As of June 2020, the paid versions are, I think, hardly comparable. For 12.50 USD per user, MS Teams comes as an integral, fully compatible part of a complete Office 365 suite. If you want only Teams – Business Basic plan for 5 USD is still there.

    This makes the Slack plans – 6.67 USD (Standard) and 12.50 (Plus) look rather expensive for what advantages they offer over Microsoft product. However, some businesses may not feel the need (or be able to) use Office and so that difference is not as stark.

    One of the key reasons for Teams meteoric growth is that it is offered free of charge to those who already have Office 365 – and this potentially made thousands of businesses simply activate it with the onset of COVID-19.

    A side not about costs. Since most organizations will eventually need some cloud and document collaboration capability, let’s imagine the most typical scenario – adding GSuite to Slack. A quick calculation shows that such an option is about two times as expensive per seat as the basic Office online with Teams. For smaller companies maybe that is not a large cost in total, but for larger ones – costs add up quickly.

    One more thing – you can open a free licence account in Office. You get to log in and receive emails with it. In GSuite this is only available with a paid account (around 6 USD).

    The Verdict

    Even before COVID hit the world, Teams was catching up to Slack and overtaking it in some key metrics. While tied to Office suite has drawbacks (the UI and general usability may be lacking), it also gives Teams a lot of firepower for the price that Slack demands.

    When using Slack, you are probably still going to have to use a separate cloud (like using GSuite). And as a long-time Slack user, I do not think it integrates with such tools well enough. Even small teams need this capability, and it should be as hassle-free as possible.

    Don’t get me wrong – if I had a small, agile team that does not have huge collaboration needs, and just needs a functional and easy platform to chat – Slack may be the one. But for most organizations additional strengths of Teams will probably be worth the change in the long term.

    Dawid Bartkowiak Marketing Specialist
    Dawid Bartkowiak Content Marketing Specialist

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