In this article
- Context
- Option 1: Migrate to a Single Collaboration Platform
- Option 2: Let Slack and Microsoft Teams Coexist
- Conclusion
- FAQ
Context
Did you know that between 40,000 and 60,000 mergers and acquisitions take place worldwide every year? source)
The motivations behind these transactions vary greatly: improving operational efficiency, expanding market share, acquiring technology or patents, strengthening a brand, achieving vertical integration, or gaining access to talent.
While the reasons differ, the process is often remarkably similar: deal sourcing, NDA signing, due diligence, valuation, Letter of Intent (LOI), negotiation, signing, and closing.
However, once the deal is signed, another critical phase begins: Post-Merger Integration (PMI).
This is where strategy meets operational reality. Organizations must tackle challenges such as cultural alignment, process harmonization, financial consolidation, regulatory compliance, and, of course, IT integration.
One recurring IT challenge arises when the two companies use different collaboration platforms. A common question quickly emerges:
Should one company migrate to the other's platform, or should both solutions coexist?
In many cases, the platforms involved are Slack and Microsoft Teams.
Option 1: Migrate to a Single Collaboration Platform
A common scenario is when Company A acquires Company B and both organizations use different collaboration environments.
For example, Company A may operate entirely within the Microsoft ecosystem and rely on Microsoft Teams, while Company B, often smaller, uses Google Workspace and Slack.
Depending on the level of integration desired, companies may decide to standardize on a single platform and migrate users, conversations, and collaboration workflows. Several specialized vendors have extensive experience supporting these migrations.
It's also important to remember that Slack and Teams are not strictly tied to Google Workspace or Microsoft 365. Many organizations successfully run Slack within a Microsoft environment, and some even use Teams alongside Google Workspace.
The most straightforward approach to collaboration after an acquisition is often to migrate everyone to a single platform.
Microsoft even provides a free Slack-to-Teams migration tool, although it does not migrate direct messages (DMs).
Once the migration is complete, employees from both organizations can collaborate seamlessly within the same platform, whether under a shared tenant or across multiple tenants.
Pros
- A unified collaboration environment across both companies
- Potential cost savings if the less expensive platform is retained
- Simpler IT support and administration
- Users generally adapt well after the initial transition period
Cons
- Requires specialized IT expertise or external consulting support
- Certain data may not be migrated, depending on the chosen solution (for example, DMs)
- Can be perceived as an imposed change by the organization required to migrate
- Requires user training and onboarding
- Existing integrations, automations, workflows, and reports may need to be rebuilt
- Some applications exist only on Slack or only on Teams
- External conversations and shared channels may be disrupted or lost
While standardizing on a single platform may appear to be the obvious choice, it comes with both short-term and long-term costs. Some challenges are temporary, such as migration efforts and training. Others can have lasting consequences, including lost integrations, unsupported workflows, and disrupted communication with external partners still using the previous platform.
This is why many organizations are now evaluating an alternative approach: coexistence.
Option 2: Let Slack and Microsoft Teams Coexist
Instead of "forcing" a migration, organizations can choose to let both platforms continue operating while enabling communication between them.
A few years ago, this approach would have been difficult to justify. Employees using Slack and Teams would have been isolated from one another, or users would have needed to work in both platforms simultaneously.
Today, this limitation no longer exists.
With a bridging solution such as convly, Slack and Teams users can communicate seamlessly while continuing to use their preferred platform.
For example, a company using Slack can continue to benefit from its existing integrations, workflows, and external Slack conversations. At the same time, employees can search for Teams users, start direct messages, and collaborate together in shared cross-platform channels.
From the Teams user's perspective, Slack users simply appear as regular Teams contacts, providing a familiar and natural experience.
This is made possible by convly's technology, which mirrors users and conversations between Slack and Teams in real time.
Pros
- Users keep their existing collaboration platform
- No migration project to manage
- No need to rebuild applications, workflows, or automations
- Existing external communications remain intact
- Minimal change management effort
- Faster collaboration between merged organizations
- Experience on Teams is 100% “natural”
Cons
- Requires additional licenses (convly and, in some cases, Teams licenses)
- IT teams must maintain knowledge of both platforms
- Experience on Slack is slightly different from standard one.
Conclusion
IT leaders are fortunate to have far more options today than they did just a few years ago. Not long ago, the idea of seamlessly connecting collaboration platforms such as Slack and Microsoft Teams seemed almost impossible. In the context of a merger or acquisition, organizations were often left with a single option: migrate one company's users entirely to the collaboration platform used by the other.
Today, there is a credible alternative to this often disruptive approach: coexistence. Solutions such as convly enable organizations using Slack and Microsoft Teams to collaborate seamlessly while allowing each company to continue using its preferred platform.
Rather than forcing users through a complex migration project, coexistence offers a more flexible path that preserves productivity, minimizes disruption, and accelerates post-merger integration.