Best practices for Microsoft 365 guest access management

Adding guest users to Teams, SharePoint, or another M365 environment can help get work done faster and more efficiently. But opening the door to too many external accounts can also quickly turn into a permissions nightmare.

Juggling who can view and edit what can definitely get overwhelming, but Microsoft 365 guest access management doesn’t have to be a headache. To help, we’ve outlined practical strategies and tools you can use to keep external collaborators visible and stay in control of your environments. 

Understanding Microsoft 365 guest users and permissions

A guest user in M365 is someone outside your company with access to your environments. Unlike internal accounts, guest accounts have limited access and are subject to tighter controls. Here’s how different M365 apps handle external access:

• SharePoint: Guests can access sites, folders, and files. Site owners set what accounts can view or edit.
• Teams: Guests are typically added to a team, then can participate in the team’s channels, conversations, and files. Private channels can include guests as long as they’re already members of the team.
• Microsoft 365 groups: Guest access can be enabled or disabled by admins. When switched on, a group member can invite guests to the Microsoft group with the group owner’s approval . This is mainly for accounts that require wider access, rather than platform-specific permissions. 

While each platform features specific guest user controls, Entra ID is where general account authentication and management happen.

Common challenges in managing guest access

Managing guest users across several apps and platforms in a compliant manner can be tricky. Here are a few common pitfalls you might run into.

Uncontrolled sharing across SharePoint and Teams

Without careful management, SharePoint and Teams guest access can cause files and folders to spread much further than you intended. One open-access link or misconfigured SharePoint library and guests can suddenly interact with a lot more than you’d like. As well as putting sharing controls in place, be sure to educate staff on the risks of granting unchecked access.

Limited visibility across workspaces and external users

Managing Teams channels, SharePoint sites, OneDrive accounts, and M365 groups can be a lot to juggle, but it’s important to carefully keep track of every external user. Each rogue account is a security risk, and limited visibility can make it difficult to track them all down.

Orphaned and inactive guest accounts

Old accounts from former advisors, contract workers, or clients who needed to approve something will continue to exist if they’re not manually closed. These accounts increase your attack surface. Carry out frequent guest user audits to check if anyone still has access to anything they shouldn’t.

Difficulty proving compliance in audits

Auditors need to know who has access to an environment, why, and how that access has changed over time. Thorough permissions tracking is essential, but standard Microsoft reporting tools often fall short. Look to third-party tools like ShareGate Protect to help you manage guest access properly.

Best practices for Microsoft 365 guest access management

While it’s quick to enable guest access in M365, managing external users is a long-term commitment. Here are some best practices to follow to help you maintain control.

Define and enforce guest access policies

IT likely doesn’t have the capacity to rule on every external sharing request, so well-defined access policies are key. Carefully lay out who can invite guests, the baseline access external users have, and how long their access lasts. You can also establish more specific policies, such as a particularly sensitive ShareGate library being read-only by default. 

Regularly review guest accounts

Any lingering account or user with unchecked access is a potential avenue for attack. Regularly carry out guest access audits to check that no one still has access they shouldn’t, and identify any inactive guest accounts that need to be closed. Perhaps a user was invited to the wrong Teams channel, or Outlook admins flagged an old mailbox that still includes an inactive external user—keeping environments as streamlined as possible will help with visibility and security. 

Strengthen governance with sensitivity labels

Sensitivity labels help classify and protect content by applying encryption, controlling sharing, and managing access settings so only the right people can open or share sensitive files. By combining these labels with regular reviews and robust access policies, you’ll nip oversharing in the bud before it has the chance to spiral out of control.

Educate group owners

M365 group owners have the power to add guest accounts, set permissions, and revoke access. They can either be your secret weapon for keeping guest access under control or the reason you spend half your week cleaning up messes.

Clear, actionable rules—like “Review and remove guests who haven’t logged in for 30 days”—work best when IT backs them up with Entra access reviews (so inactivity can actually be measured and acted on consistently).

How ShareGate helps manage Microsoft 365 access governance

ShareGate Protect helps you see how access and sharing actually work across Microsoft 365, so you can spot oversharing, guest access drift, and workspace clutter before they turn into bigger problems.

Instead of jumping between admin centers or relying on scripts, you get one place to understand what’s happening and take action.

Unified visibility across Microsoft 365 

ShareGate Protect brings key governance signals into one view across SharePoint, Microsoft Teams, OneDrive, and sharing links. You can quickly identify broad access, external sharing, and guest access patterns that are easy to miss when everything is spread across different tools.

Built-in remediation you can act on immediately

Finding risk is only half the job. ShareGate Protect lets you resolve common access issues directly from the view you’re in. 

Use guided, in-context actions and bulk remediation to tighten sharing, clean up access drift, and reduce exposure without the need to hop between admin centers or write custom scripts.

Reporting that helps you prove progress

ShareGate Protect supports ongoing governance with clear reporting you can use for reviews, audits, and stakeholder updates. Track changes over time, share what was fixed, and show that governance work is happening continuously—not just during one-off cleanups.

Strengthen guest access governance with ShareGate

Guest access helps teams collaborate, but it’s easy for external users, old links, and unclear ownership to linger. ShareGate Protect helps you monitor where exposure exists, prioritize what needs attention, and take action to reduce risk across Microsoft 365.

Discover how ShareGate Protect turns visibility into action by requesting a demo today.