What is the Difference Between Yammer and Slack?

Here is an introduction to Yammer and Slack, head to head.

During the coronavirus pandemic of 2020, online collaboration tools grew from luxuries to necessities. Millions of entrepreneurs, business people, educators, and nonprofits, forced to work from home, turned to Zoom, Microsoft Teams, Yammer, and Slack.

Here is an introduction to Yammer and Slack, head to head.

Yammer vs. Slack

Yammer, founded in 2008 by David Sacks, bills itself as the “enterprise social network,” aka “Facebook for your company.” For some people that will sound awesome and, for others, a fate worse than death.

Microsoft, which bought Yammer in 2012 for $1.2 billion, later launched Teams in 2017. Both leverage the Office 365 platform, and Teams has grown into the business world’s most-used collaboration tool. Microsoft invites users to integrate Yammer into Teams.

Yammer Feed

Stewart Butterfield founded Slack five years later, in 2013, as an easy to set up and use cloud-based platform. Slack boasts high-end data security like 2FA and SSO to protect an organization’s vital information.

While Slack may be better for real-time conversations, like collaborators on a project, Yammer might be better for posting information – like to a far-flung sales team who want to talk shop in a free-ranging, over lunch or coffee kind of way.

Yammer vs Slack UI/UX

While Yammer’s is simple, Slack’s is more appealing, most reviews say. Both are web-based. Channels and Notifications are similarly effective.

Yammer doesn’t manage by time zones, but Slack does. Both are available on Mac OS, Windows, Linux, iOS and Android.


When it comes to third-party integrations, Yammer’s got the powerful Microsoft Office 365 as an ally – especially SharePoint. Slack,meanwhile, works with over 1200 apps. When it comes to these third-party integrations, Slack used to hold a big advantage over Teams and other Microsoft tools – but that has changed somewhat.

While paid Slack allows you to use all these integrations directly, the free plan limits that to ten. Microsoft on the other hand, has an App Studio where you can design your own Teams apps. And again, Yammer can be integrated into Teams.

Video Calls

On Slack, up to 15 can join with voice, video, and screen-sharing. Yammer works through Microsoft Stream, as well as through 3rd party apps like GoToMeetings, Google Hangouts & more.

You can also use Zoom via Microsoft Teams, or the Teams video.


Teams offers more storage, which Yammer can utilize (I think) 10GB per user storage in the free version, versus 5GB for Slack.

For its paid versions, Slack goes up to 20GB while Yammer – via a paid Teams account - offers a massive 1TB (1 terabyte = about 1,024GB).

File Sharing and Collaboration

Yammer, through Microsoft Teams, lets you share Office 365 files and work on them immediately from the workspace.

Slack doesn’t come with the option of editing documents from the workspace, so you have to download files and open them in specific apps to edit them.

Frequent new updates based on customer feedback

The Microsoft client companies providing feedback are overwhelmingly larger companies. Recent updates include a “hand raising” feature, useful in large meetings and group calls.

Teams also offers offline and low-bandwidth support -more important than ever as pandemic pushes work from home onto older, more marginal internet connections, and binge-watching push work limits of bandwidth like never before.

Task management

While Microsoft Teams requires integration with the Planner tool, it can more easily handle workers and companies who use multiple shifts.


Yammer from Office 365 comes with enterprise-level security, and compliance to provide secure online space for business enterprises, whereas the basic version doesn’t extend any admin security controls. All conversations and feeds in transit and at rest are encrypted with AES-256-bit key encryption.

Yammer data is totally secured under strict guidelines at Microsoft’s global network of data centers with round the clock video surveillance, bio-metric and pin-based locks, strict personal access controls, and detailed visitor entry logs. All work-spaces data is super-secured at Slack. It does provide safety to data through security bots.

Slack is a certified ISO/IEC 27001, ISO/IEC 27017, ISO/IEC 27018 and HIPAA accredited team collaboration business chat application. Slacks GDPR policy is made available for the users at their website. The other security features include;SAML-based SSO, SCIM provisioning, Granular app management, Custom Message Retention, Slack Enterprise Key Management (Slack EKM) and Support for DataLoss Prevention (DLP).


Both Slack and Yammer have freemium plans. Slack’s pricing: $6.67 per person per month for smaller businesses, or $12.50/month or larger ones, billed annually. It’s a bit higher billed monthly.

Slack offers special pricing through Enterprise Grid for the largest businesses – up to 500,000 users - and those in regulated industries, based on billing annually. Yammer’s paid plans start at $3.00 per user per month.

Help & Support

Both Slack and Yammer provide help and support through different channels like bots and FAQs. Here is Slack’s help and support page, while Yammer’s help goes through Microsoft.

Final Thoughts

These are specific tools for specific jobs and collaborations. Our advice is to think about the jobs you need it for when picking the collaboration tool – if you need one.

Slack, newer and not owned by Microsoft, tends to earn slightly higher subjective reviews. And if you’re thinking Yammer, you might also think about just getting Microsoft Teams.

You can learn more about Microsoft Teams compared to Slack here.

Switch4Teams Ltd is a UK-based, award-winning Unified Communications provider with over 20 years of experience.

Our voice over IP (VoIP) internet-based telephony, Microsoft Teams Direct Routing and UC cloud communication solutions are currently used by 1,000’s of SMEs and partners across the UK.

Contact us by email at info@switch4teams.com or call +44.0113.328.1330

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