Slack to Teams Migration Guide for IT Admins

1. Introduction

Migrating from Slack to Microsoft Teams means transferring your organization’s channels, direct messages, files, threads, emojis, timestamps, and deep messaging context from Slack’s workspace model into Teams’ channel and chat architecture.

A successful migration requires choosing the right approach based on your data scope. Microsoft now offers a free native migration tool in the Microsoft 365 admin center, but it only covers channel content and does not migrate direct messages, workflows, etc.

Organizations that need to migrate Slack channels to Teams along with direct migration and complete messaging, metadata, and context require a third-party migration tool like CloudFuze.

This guide walks IT admins through the full scope of a Slack to Teams migration, including the planning process, key challenges, how to migrate using CloudFuze’s platform, and what to do after the migration is complete.

To quickly get started, you can also watch this migration video:

2. Slack to Teams Migration: What IT Admins Need to Know in 2026

The Slack to Teams migration landscape has changed significantly in 2026. Microsoft launched a native migration tool inside the Microsoft 365 Admin Center which has broken the entry barrier for smaller organizations to start a channel-only migration.

However, understanding what the tool does and does not cover is now one of the most important decisions an IT admin can make before planning the migration.

What Microsoft’s native tool covers

Microsoft’s built-in Slack to Teams migration tool, which reached general availability in early 2026, can migrate:

• Public and private Slack channels
• Channel messages, including threads and standard reactions
• Channel file attachments
• Channel canvas and list content
• Channel membership (owners and members)

What Microsoft’s native tool does not cover

The native tool has significant gaps that affect most enterprise migration projects.

• Direct messages are not supported. The tool migrates only channel content. One-to-one and group DMs are left behind.
• Only one Slack workspace can be connected at a time, which makes multi-workspace enterprise migrations complex.
• Delta migration is not supported. Incremental changes made during the migration window cannot be synced after the initial transfer.

For organizations that only need to transfer Slack channels and can accept losing direct message history, Microsoft’s free tool may be sufficient. For any organization that needs to transfer Slack to Microsoft Teams completely, including DMs, timestamps, pinned messages, and multi-workspace environments, a purpose-built third-party tool is required.

3. Slack to Teams Migration Trends and Use Cases

Microsoft Teams now has a significantly more number of monthly active users compared to Slack. The gap has widened as organizations increasingly consolidate their collaboration stack around Microsoft 365.

The decision to migrate Slack to Microsoft Teams is no longer primarily a platform preference decision for most enterprises. It is driven by license consolidation, AI readiness, and the pressure to standardize on one ecosystem.

The most common use cases we see at CloudFuze:

a. Microsoft 365 Consolidation

Organizations already running SharePoint, OneDrive, Exchange, and Outlook, are moving away from Slack to reduce redundant licensing costs and consolidate all collaboration under the Microsoft 365 ecosystem. Teams is included in most Microsoft 365 plans, which means Slack becomes an additional cost that many CFOs want eliminated.

b. AI Readiness and Copilot Adoption

Organizations rolling out Microsoft 365 Copilot need their collaboration history inside the Microsoft 365 ecosystem for Copilot to surface it. Conversations, files, and threads that remain in Slack are invisible to Copilot. Therefore, migrating Slack to Teams becomes a prerequisite for organizations that want Copilot to have full context of their team’s work history.

c. Mergers and Acquisitions

When two organizations merge and one runs Slack while the other runs Teams, IT teams need to migrate Slack channels to teams while preserving historical context, including messages, threads, user mapping, and more, so that the merged team can operate from a single platform

d. Government and Compliance-Driven Migration

Organizations in regulated industries such as healthcare, finance, and government, are migrating away from Slack to leverage Teams’ advanced compliance capabilities, including eDiscovery, retention policies, and Microsoft Purview integration.

4. Slack vs. Microsoft Teams: Key Differences for IT Admins

Before planning a Slack migration to Teams, IT admins need to understand the structural differences between the two platforms. These differences affect how channels map during migration and how users adapt post-migration.

NOTE: This comparison table draws information from June 2026 data. It may change when Slack and Microsoft update product features.

5. Key Differences when Transitioning from Slack to Teams

Understanding how channels and conversations work in Slack and Microsoft Teams is important before finalizing the migration plan.

In Slack, channels are designed to be flexible spaces for group discussions and are well suited for short-term or informational communication. In Teams, channels are structured spaces built for organized, long-term group conversations, organized within a parent team.

This means that when you migrate Slack channels to Teams, you are not just moving messages, you are moving them into a more structured hierarchy. Preparing users for this shift is just as important as the technical migration itself.

A few practical differences to communicate to your users before starting the migration:

• Threading is the norm in teams: Encourage users to reply within threads rather than posting stand-alone messages in a channel, which preserves context and makes channels easier to navigate.
• Channels live inside teams not at the top level: Users who are used to a flat list of Slack channels will need to adjust to the Teams folder-style hierarchy.
• Conversations in Teams tend to be more formal and threaded: Rapid back-and-forth conversations that happen in Slack DMs typically shift to Teams chats post-migration.

6. Major Slack to Teams Migration Challenges

Migrating from Slack to Microsoft Teams comes with technical and operational challenges. Understanding them before the project starts helps IT admins build a realistic plan.

a. Microsoft’s native tool does not migrate direct messages

This is the most significant challenge for many organizations in 2026. Microsoft’s built-in migration tool, now available in the M365 admin center, only migrates channel content.

Direct messages, which often contain important decisions, file exchanges, and sensitive team communication, require a third-party tool to migrate. CloudFuze is one of the few migration platforms that fully support DMs migration, including message history, timestamps, and attachments.

b. API rate limits and data volume

If your Slack data volume is large, you are at higher risk of hitting Microsoft API rate limits during migration, which can cause data loss or incomplete transfers. A managed migration service with dedicated infrastructure handles rate limiting automatically and monitors the migration in real time.

c. More than 200 channels in a single workspace

Microsoft Teams supports up to 200 channels per team. Organizations with Slack workspaces that exceed 200 channels need to plan for distributing those channels across multiple Teams, consolidating inactive channels before migration, or both.

d. Unsupported characters in file names

Slack allows file names and special characters that Microsoft 365 does not support. Without automated handling, these files fail to migrate or land with corrupted names. CloudFuze automatically identifies files with unsupported names or special characters and replaces them with underscores or hyphens to ensure clean migration.

e. User mapping complexity

Aligning Slack user accounts with Microsoft 365 user accounts requires accurate mapping, especially in M&A scenarios where email domains differ. Having a proper plan to map users manually in CSV formats with expert support plays an integral role.

f. Maintaining business continuity during migration

Larger organizations cannot afford to pause Slack access while migration is in progress. CloudFuze migrates messages in the background, which allows users to continue using Slack while the transfer happens. The tool then captures incremental changes through Delta sync.

7. Planning Slack to Teams Migration

A proper plan lays a solid foundation for a successful Slack to Teams migration journey. The planning phase determines scope, surfaces risks early, and aligns IT teams and stakeholders before any data moves.

a. Pre-Migration Analysis

One of the most important stages of any Slack to Teams migration is pre-migration analysis. With a proper pre-migration analysis, you can determine what needs to be migrated and plan the scope of work accordingly.

When performing a pre-migration analysis, make sure to focus on these parameters:

• Check the total number of channels (public and private) to migrate
• Check the total number of users to migrate
• Number of direct messages and group messages to migrate
• Types of message metadata to preserve (timestamps, threads, reactions, pins)

This analysis shapes the migration tool selection, timeline, and whether phased batches are needed.

b. Decide Which Content and Channels to Retain or Leave

One of the most important decisions to make when planning a Slack to Teams chat migration is to finalize which Slack content and channels to transfer and which ones to leave. Here are some of the important steps to take:

• Review channel activity: Understand user activity in each channel and check for metrics like message volume, member participation, last activity date, and more. This helps you differentiate active channels from idle ones.
• Get input from channel owners: By taking inputs from channel owners, admins, and department leads, you can understand which channels are important for ongoing operations.
• Consolidate overlapping channels: If you have similar or overlapping Slack channels, it’s best to merge their content to make the overall scope of migration lightweight.
• Differentiate must-haves from nice-to-haves: Not all channels and content may be important. By checking all channels, understand which ones are important and which ones are not. You can then archive the less important channels.

c. Communicate with Stakeholders

Communications with users and stakeholders is the most commonly overlooked part of migration planning. Build a communication plan that addresses:

• When the migration will happen and in what phases
• What users need to do before the cutover date
• What will and will not be migrated
• Where to go for support during and after the transition
• Training resources for Teams adoption

8. Preparing for the Migration

Proper preparation lays a solid foundation for complete Slack to Teams migration success. Here are some of the most important preparation steps to take:

a. Choosing a Slack to Teams Migration Tool

The right Slack to Teams migration tool depends on your organization’s specific requirements. For channel-only migrations with a small number of users and no DM requirements, Microsoft’s native admin center tool may be sufficient.

For enterprise migrations that need to transfer Slack to Microsoft Teams completely, including DMs, pinned messages, user group mappings, timestamps, and multi-workspace support, a purpose-built platform like CloudFuze is necessary.

Key evaluation criteria:

• Does it migrate direct messages?
• Does it support delta migration?
• Is it SOC 2 Type 2 certified?
• Can it handle more than 200 channels per workspace?
• Does it support non-admin private channel migration?
• What is the deployment model (SaaS, dedicated instance, customer cloud)?

b. User Mapping

With proper user mapping, your company can ensure 100% accuracy during the chat migration process. When creating CSV mappings, make sure to use proper syntax and folder paths to avoid inaccuracies.

Also, validate the CSV user mapping paths with the migration partner before adding them to the migration tool.

c. Admin Login Details

You must be ready with the login details when adding and authenticating your company’s Slack and Microsoft Teams cloud. Make sure that you or your team members have quick access to the Primary Workspace owner’s login details for Slack and Global Admin’s login details for Teams.

d. Managing Access to Slack When Migrating to Teams

CloudFuze’s Slack to Teams migration tool transfers chat messages in the background which allows users to continue using Slack. The incremental changes made during the one-time migration can then be migrated using CloudFuze tool’s delta migration feature.

It is also important to set a clear cutover date and schedule it after the migration completion and validation phase.

e. Preparing Users for Transitioning from Slack to Teams

Apart from the IT team and other stakeholders, the end-users must also be ready for the chat platform transition. But how do you do this? Consider some of these approaches to help them get ready:

• Evangelize about the platform transition:Help users understand the benefits of making the chat platform switch. A clear understanding of the migration’s reasons and benefits can help users become ready.
• Ensure extensive user training: Providing structured training to users helps them understand the chat functionalities of Microsoft Teams. This way, they can smoothly adjust to the changes in configurations and workflows post-migration.
• Share Teams adoption resources: Apart from training, it is also important to share Teams adoption resources to help users onboard smoothly without any impact on their workflows and productivity.

9. CloudFuze’s Slack to Teams Migration Tool

CloudFuze enables large enterprises, mid-market organizations, and MSPs to migrate Slack to Microsoft Teams with complete data coverage and enterprise-grade security.

As a Microsoft Migration Partner listed on Microsoft AppSource, CloudFuze is one of the only platforms in the industry that migrates direct messages, timestamps, pinned messages, user groups, non-admin private channels, emojis, and all other context alongside channel content.

Unlike Microsoft’s native tool, CloudFuze supports multi-workspace migrations, delta migrations, and time period filtering, giving IT admins precise control over what gets migrated and when.

10. CloudFuze Platform Features

CloudFuze migrates all core Slack data types to their equivalent destinations in Microsoft Teams.

What CloudFuze migrates:

• Public and private channels (mapped to Teams channels)
• Direct messages (one-to-one chats)
• Group direct messages (group chats)
• Channel members and user groups
• Threads, @mentions, and replies
• Attachments and files
• Emojis and reactions
• Pinned messages (including DM pinned messages)
• Timestamps for channels and direct messages
• Text formatting (bold, italic, strikethrough, numbered lists, bullet lists)
• Code blocks (migrated as formatted text)

Migration modes:

• One-time migration
• Delta migration (for capturing incremental changes)
• Time period filtering (example: last three years only)

Technical specifications:

• RESTful API platform with cloud-native architecture
• OAuth 2.0 authentication for Slack and Microsoft 365
• RSA 2048 encryption for all data in transit
• SOC 1 and SOC 2 certified US-based data centers
• Deployment options: SaaS for small migrations, dedicated instances for large migrations, or deployable in customers’ cloud or data center (intended for enterprises, universities, and government agencies).

11. How Slack Data Maps to Microsoft Teams

When CloudFuze transfers Slack to Microsoft Teams, data maps as follows:

A note on file names: Slack permits file names and special characters that Microsoft 365 does not support. CloudFuze automatically identifies files with unsupported names or characters and replaces them with an underscore or hyphen to ensure all files land cleanly in SharePoint without errors.

12. Slack to Teams Migration Case Studies

As a Microsoft Migration Partner, we at CloudFuze have helped many companies migrate from Slack to Microsoft Teams with our solutions tailored to their use cases. Here’s one such example:

Case Study highlights: Stryker, a leading medical technology company, had acquired a company and wanted to selectively move their Slack users to Teams. With our solutions, they were able to sort through a vast pool of users, strategically select and map them, and migrate them over to the existing Teams environment. Explore the Stryker case study to dive deep into more details.

CloudFuze’s Slack to Teams migration approach has also been cited in industry coverage as an example of how enterprise migrations should be handled. Read the UC Today case study coverage.

Our dedicated experts can help your team carry out a strategic Slack to Teams migration project without disrupting your business operations. For more details on how to migrate your business data from Slack to Teams, contact our migration experts.

13. Security

CloudFuze is trusted by large enterprises and US government agencies for Slack to Teams migration. All data in transit is protected using RSA 2048 encryption.

Migrations are executed via API calls, which means your SaaS data is never written to CloudFuze’s servers. The data moves directly from source to destination. CloudFuze operates from SOC 1 and SOC 2 Type 2 certified data centers in the United States.

For organizations in regulated industries, CloudFuze also supports deployment inside the customer’s own cloud environment or data center, which gives IT and security teams full control over where the migration process is run. Read more about CloudFuze Security.

14. Benefits for Companies and IT Admins

The following are the benefits that companies and IT teams get when choosing CloudFuze as the migration partner.

a. Complete data migration, nothing left behind

CloudFuze migrates channels, direct messages, files, timestamps, threads, emojis, pinned messages, user groups, and more. Some of these data types are not supported by Microsoft’s native tool and many competitors.

b. No disruption to existing workflows

Migration runs in the background. Users continue working in Slack until the cutover date, and delta migration captures all changes made during the one-time migration stage.

c. Microsoft 365 Copilot readiness

Migrating your organization’s Slack history into Teams puts all your collaboration data inside the Microsoft 365 ecosystem and makes it accessible to Microsoft 365 Copilot. So, the migration is not just about transferring chat data but also now about being AI ready.

d. Licensing cost reduction

Consolidating on Microsoft Teams eliminates Slack subscription cost. For organizations on Microsoft 365 enterprise plans, Teams is already included which makes the ROI on migration immediate.

e. Enterprise-grade security and compliance

SOC 1 and SOC 2 Type 2 certified infrastructure, RSA 2048 encryption, and flexible deployment options meet the security and compliance requirements of regulated industries and government agencies.

f. Managed migration service

CloudFuze’s team handles the migration end-to-end via a managed migration service, which reduces the load on internal IT teams and helps ensure the project is completed on time and within scope.

15. CloudFuze vs. Competitor Migration Tools

Compared to Microsoft’s native tool and other migration tools, CloudFuze provides broader migration scope coverage by supporting direct message migration, preservation of intricate messaging metadata and context, and flexibility for more deployment options. Here is a comparison.

16. How to Migrate from Slack to Microsoft Teams

These steps show how IT teams can use CloudFuze to migrate Slack to Teams along with channels, direct messages, users, files, and other features. The following are the prerequisites for the migration.

• Slack admin login credentials
• Microsoft 365 (Office 365) admin login credentials
• A CloudFuze account

Don’t hesitate to get in touch with our migration team for a quote or to request a trial.

1. Log in to CloudFuze

Go to webapp.cloudfuze.com and create a CloudFuze account. We offer a limited 30-day trial account for users who want to test the service. IT administrators can reach out to our migration team for a live demo or quote.

2. Add Your Slack Account to CloudFuze

Locate the Slack cloud in the business clouds list and click on it. A popup will appear where you need to enter Slack account details.

3. Enter Slack Login Credentials

Enter your company’s Slack login details and click on the Sign-in button.

4. Provide Access to CloudFuze

Click on the Allow button to provide access to CloudFuze.

5. Add Microsoft Teams to CloudFuze

Click on the Microsoft Teams cloud that you can see in the business clouds list.

6. Authorize Microsoft Teams

Click on the Accept button to complete the authorization process.

7. Verify Whether Slacks and Teams Are Added

Click on the Clouds tab and go to the Manage Clouds tab. If successfully added, both Microsoft Teams and Slack accounts will be displayed there.

8. Click on the Slack Migration Tab

Click on the Slack migration tab in the navigational menu on the left and click on it.

9. Select the Source and Destination Clouds

Since it is a Slack to Microsoft Teams migration, we need to select Slack as the source and Microsoft Teams as the target/destination cloud. Ensure to get the sequence right. The wrong choice will end up migrating Team’s content (if any) to Slack.

10. Select the Users to Migrate

Our Slack to Microsoft Teams migration solution maps users automatically based on their email aliases. IT admins can still migrate users’ chats, channels, and workspaces to Teams irrespective of the auto-map list.

11. Select Workspaces and Start the Migration

CloudFuze pulls and displays the list of all workspaces in your Slack account. Click on the Channels tab next to Users to view all of them. Check the Private Workspaces. Now, click on the Private option to view all the Private workspaces in your Slack account. Once done, start the migration process.

12. Slack to Microsoft Teams Migration Is in Process

Go to Reports and check for the status of the migration. During the chat migration process, the status will be displayed as In Progress.

13. Migration Has Been Completed Successfully

Once the migration is completed, the status will be changed to Processed from In Progress.

14. Select Direct Messages

Our tool maps users automatically and migrates Slack direct messages to Teams with all the features.

15. Messages Are Being Migrated

By clicking on the Next button, direct messages will migrate from Slack to Teams.

16. All the Direct Messages Have Been Migrated

When all the DMs are migrated, CloudFuze displays the status as Processed. Users can log into their Microsoft Teams accounts to validate whether all messages are properly migrated.

Conclusion

Migrating from Slack to Teams in 2026 is a more nuanced decision than it was two years ago. Microsoft’s native migration tool makes it easier to migrate channel content for free, but organizations that need to transfer Slack to Microsoft Teams completely, including direct messages, and full metadata and context, still require a purpose-built tool.

CloudFuze covers the full migration scope while providing enterprise-grade security, managed migration options and a proven track record across large enterprises and government migrations.

Contact us today to learn how we can tailor our solutions to meet your company’s Slack to Teams migration requirements.

Frequently Asked Questions

1. How do I migrate from Slack to Microsoft Teams?

To migrate from Slack to Microsoft Teams, you need to connect both your Slack workspace and your Microsoft 365 tenant to a migration tool, map users, select the channels and direct messages to migrate, and run the migration.

2. Can Microsoft’s free Slack migration tool migrate direct messages?

No. Microsoft’s native Slack to Teams migration tool only migrates channel content, including public and private channels, channel messages, and channel files. To migrate Slack direct messages, group direct messages, and rich metadata and context, organizations need to use the third-party migration tool like CloudFuze that has API-level access to direct messages and the ability to map them to Teams personal chats.

3. How Much Does It Cost to Migrate from Slack to Teams?

The cost to manage Slack to Teams depends on the number of users, the volume of data (messages and files), the level of metadata preservation required, and whether you want to use Microsoft’s free native tool or a third-party platform. Microsoft’s admin center tool is free but limited to channels. CloudFuze pricing is scoped based on user count and data volume.

4. How long does a Slack to Teams migration take?

Migration time depends on data volume, the number of users, and the number of messages and files. Small migrations (under 500 users with monitored data) typically complete within a week. Large enterprise migrations can take several weeks and months, particularly when data migration and validation phases are included.

5. Does CloudFuze migrate direct messages?

Yes. CloudFuze migrates Slack direct messages to Microsoft Teams along with message history, timestamps, attachments, replies, reactions, user mentions, pinned messages, and more.

6. Does CloudFuze migrate timestamps?

Yes, CloudFuze migrates timestamps of public/private channels and direct messages between users. Timestamps for groups can also be migrated.

7. Does CloudFuze migrate Slack files?

Yes. CloudFuze migrates all files from Slack channels and direct messages to Microsoft Teams. Channel files land in the associated SharePoint library. Files with names containing special characters that are unsupported by Microsoft 365 are automatically renamed using an underscore or hyphen to ensure a clean transfer.

8. How secure is CloudFuze for Slack to Teams migration?

CloudFuze is trusted by large enterprises and U.S. government agencies. All migration data travels via API calls using RSA 2048 encryption. CloudFuze operates from SOC 1 and SOC 2 Type 2 certified data centers in the United States and supports deployment inside a customer’s own cloud or on-premises infrastructure for organizations with strict data residency requirements.

9. How to Check the number of users in a Slack account?

Log in to your Slack account. Please keep in mind that you must log in as admin to retrieve the user’s info. Go to Settings & Administration and click on the Workspace Settings option.

From the Administration menu, click on the Manage Members tab. All the user’s information will be displayed there.

10. How to check file data metrics in a Slack account?

Slack primarily shows the data of the number of messages sent and the number of files. It doesn’t show the data size in GBs or TBs. To check the metrics, click on the Tools option from the main menu and click on Analytics.

Click on the Messages Sent or Files Uploaded tabs to check concerned analytics.

11. How to contact CloudFuze?

You can chat with our migration team by clicking on the chat button on the bottom right corner of this page. Alternatively, you can submit your query, and our team of experts will contact you.

12. Can you migrate data from Slack to Teams?

Yes, CloudFuze can migrate data from Slack to Teams. In addition to migrating Slack channels and direct messages, our tool can also transfer files from Slack to Microsoft Teams.

13. How to migrate direct messages from Slack to Teams?

Currently, there is no manual option or free Slack to Teams migration tool that can migrate direct messages from Slack to Teams. CloudFuze is the only complete solution in the world that can migrate a lot of Slack features to Microsoft Teams.

14. How secure is CloudFuze’s Slack to Teams migration platform?

CloudFuze is highly secure. The platform has been used by some of the world’s biggest enterprises and government agencies. Find out more about CloudFuze security.

15. What level of support does CloudFuze provide?

Each business migration at CloudFuze gets a dedicated migration team with a migration manager. CloudFuze is highly known in the industry for its managed migrations.

16. What are the prerequisites for Slack to Teams migration?

In order to migrate from Slack to Teams, you must be a Slack admin or have Slack admin login credentials. You must also have admin access to the Microsoft 365 account.