How to Add and Remove Microsoft 365 Licenses Without Losing Data

Removing a Microsoft 365 license from a user account is one of those tasks that sounds simple until you realize you do not know what happens to their data. Does their email disappear? Are their OneDrive files deleted? Do their Teams messages vanish? The answer depends on what type of license is being removed, whether you are removing or reassigning it, and how long you wait before taking the next step. This guide covers what actually happens to data when you remove a license, how to preserve everything you need, and how to audit your licenses so you stop paying for seats nobody is using.

What happens when you remove a license

When you remove a Microsoft 365 license from a user account, Microsoft does not delete their data immediately. There is a grace period, but the length of that grace period and what happens during it depends on the service.

Exchange Online (email)

When the license is removed, the mailbox is disconnected from the user account but not deleted. Microsoft retains the disconnected mailbox for 30 days. During this period, a Global Admin or Exchange Admin can reconnect it by reassigning a license to the same user account, and all email, contacts, and calendar data will reappear.

After 30 days, the disconnected mailbox is permanently deleted. There is no recovery after this point. If you need the mailbox data longer than 30 days, you must either keep the license assigned, convert the mailbox to a shared mailbox before removing the license, or export the mailbox to a PST file.

If the mailbox is on litigation hold or an eDiscovery hold, the data is retained beyond the 30-day grace period regardless of license status. The hold takes precedence. This is relevant for businesses with legal or compliance requirements.

OneDrive

When the license is removed, the OneDrive files are retained for 30 days by default. The user’s manager (as set in Azure AD/Entra ID) automatically gets access to the OneDrive contents during this period. If no manager is set, the Global Admin can access the files.

After 30 days, the OneDrive data is queued for permanent deletion. The actual deletion happens within the next 14 days, so there is effectively a 30 to 44 day window before the data is gone for good. A third-party backup solution eliminates this risk entirely by retaining copies of OneDrive data regardless of license status.

You can change the OneDrive retention period in the SharePoint admin center under Settings > OneDrive > Retention. The default is 30 days, and you can extend it up to 3,650 days (10 years). If you regularly have employee transitions and need more time to sort through files, increasing this to 90 or 180 days is a reasonable precaution.

SharePoint

SharePoint site content is not tied to individual user licenses. Removing a user’s license does not affect files stored in SharePoint team sites or the document libraries behind Teams channels. Those files belong to the site, not the user.

If the user was the site owner or the only site collection administrator, removing their license does not delete the site, but it does leave the site without an active owner. Assign a new owner before or immediately after removing the license to prevent management issues.

Microsoft Teams

Teams messages and channel content are stored in the team’s SharePoint site and Exchange group mailbox, not in the individual user’s account. Removing a user’s license does not delete their messages from team channels.

One-on-one chat history is tied to the user’s mailbox. If the mailbox is preserved (by converting to a shared mailbox or keeping the license), the chat history remains accessible through eDiscovery. If the mailbox is deleted after the grace period, the chat history for that user’s side of the conversation is lost.

Microsoft 365 Groups

If the user owned Microsoft 365 Groups and you remove their license and later delete their account, Groups with no remaining owners become ownerless. Ownerless Groups can still function, but nobody can manage their settings. Assign new owners to any Groups the user owns before removing the license.

How to remove a license without losing data

The safe approach depends on what you need to preserve.

Scenario 1: Employee left, you need to keep their email accessible

This is the most common scenario. The employee’s email needs to remain accessible to their team or manager, but you do not want to keep paying for a license.

1. Convert the mailbox to a shared mailbox in the Exchange admin center
2. Grant access to the appropriate users (their manager, a team lead, or a department inbox owner)
3. Remove the Microsoft 365 license from the account

A shared mailbox does not require a license as long as it stays under 50 GB. The email, contacts, and calendar data are preserved indefinitely. Team members with access can read and respond to messages from the shared mailbox in Outlook. This is the standard approach during employee offboarding.

The conversion must happen before you remove the license. If you remove the license first, the mailbox enters the 30-day grace period as a disconnected mailbox. You can still convert it during this window by reassigning a license, converting to shared, and then removing the license again, but it is an unnecessary extra step.

Scenario 2: Employee left, you need their OneDrive files

1. Before removing the license, go to the OneDrive admin center and set the departed user’s manager (if not already set in Entra ID)
2. Alternatively, grant a Global Admin or another user direct access to the OneDrive
3. Copy the files you need to a SharePoint document library, a team site, or another user’s OneDrive
4. Remove the license

Do not rely on the 30-day retention period to “get around to” copying files. Set a reminder or handle it during the offboarding process. Files that are deleted because someone forgot to copy them in time are gone permanently.

For large OneDrive collections, use the SharePoint admin center to directly transfer ownership rather than downloading and re-uploading.

Scenario 3: Downgrading a user to a cheaper plan

If you are moving a user from Business Premium to Business Standard (or from Standard to Basic), you are removing one license and adding another. The order matters:

1. Add the new license to the user first
2. Verify the user can still access their email, OneDrive, and Teams
3. Remove the old license

Adding before removing ensures there is no gap where the user has no license. If you remove first and then add, the mailbox may enter the disconnected state during the gap, which can cause temporary access issues even if you add the new license within minutes.

When downgrading from Premium to Standard or Basic, the user loses access to features that only exist in Premium (Defender, Intune, conditional access). Make sure this is intentional. See our Microsoft 365 licensing guide for what each plan includes.

Scenario 4: Temporarily removing a license (seasonal worker, leave of absence)

If an employee is going on extended leave and you want to stop paying for their license during that period:

1. Convert the mailbox to a shared mailbox (preserves email without a license)
2. Copy any OneDrive files that need to remain accessible to SharePoint
3. Remove the license
4. When the employee returns, assign a new license and convert the shared mailbox back to a regular mailbox

This works, but it has friction. Converting back and forth between shared and regular mailboxes is not instant and can occasionally cause issues with Outlook profile caches on the user’s machine. For short absences (a few weeks), it is usually simpler to keep the license active. For extended leaves (three months or more), the savings justify the conversion.

An alternative for Premium users: Microsoft offers the option to switch to a cheaper plan during the absence rather than removing the license entirely. Downgrading to Business Basic ($6/user) keeps the mailbox active and avoids the shared mailbox conversion, at a lower cost than Premium.

Adding licenses

Adding a license to a new user

When you create a new user in the Microsoft 365 admin center, you assign a license during creation. The mailbox, OneDrive, and Teams access are provisioned automatically within minutes.

If you created the user without assigning a license (intentionally or by mistake), you can add one at any time:

1. Go to admin.microsoft.com > Users > Active users
2. Select the user
3. Click “Licenses and apps”
4. Check the box next to the plan you want to assign
5. Click “Save changes”

The mailbox and other services provision within 15-30 minutes. OneDrive may take up to 24 hours to appear the first time.

Reassigning a license from one user to another

If an employee left and you removed their license, that license is now available in your license pool. You do not need to buy a new one. Assign it to the new employee from the same Licenses and apps page.

Check your available license count at admin.microsoft.com > Billing > Licenses. This shows how many licenses you own, how many are assigned, and how many are available for each plan.

Bulk license management

For changes affecting multiple users at once (department restructure, plan upgrade for a team), the admin center supports bulk operations:

1. Go to Users > Active users
2. Select multiple users using the checkboxes
3. Click “Manage product licenses” at the top
4. Choose “Replace” to swap plans or “Add” to add an additional license

For larger tenants (50+ users), PowerShell is more efficient:

# Connect to Microsoft Graph
Connect-MgGraph -Scopes "User.ReadWrite.All"

# Get users in a department
$users = Get-MgUser -Filter "department eq 'Sales'" -All

# Assign a license to each user
foreach ($user in $users) {
    Set-MgUserLicense -UserId $user.Id -AddLicenses @{SkuId = "your-sku-id"} -RemoveLicenses @()
}

Auditing license usage

Paying for unused licenses is one of the most common sources of waste in Microsoft 365 tenants. A quarterly audit takes 15 minutes and can save hundreds of dollars per month.

Find unused licenses

In the admin center, go to Billing > Licenses. Each plan shows how many licenses are purchased versus assigned. If you own 50 Business Premium licenses and only 42 are assigned, you are paying for 8 unused seats. For a complete guide to reducing Microsoft 365 costs including right-sizing plans and eliminating redundant add-ons, see the dedicated cost optimization guide.

Find inactive users with licenses

A license assigned to a user who never logs in is as wasteful as an unassigned license. Check sign-in activity:

1. Go to Entra admin center > Users > Sign-in logs
2. Filter for users who have not signed in for 90+ days
3. Cross-reference with your license assignments

Users who have not signed in for 90 days and are not on leave should have their licenses reviewed. They may be former employees whose accounts were blocked but not properly offboarded, or they may be service accounts that do not need full user licenses.

Find users on the wrong plan

Review whether each user’s plan matches their actual usage:

• Users on Premium who never access Intune-managed devices and do not handle sensitive data may be fine on Standard
• Users on Standard who never open desktop Office apps could drop to Basic
• Users on Basic who are sending email from desktop Outlook (which requires Standard or Premium) are using a license that does not cover their actual usage, and their Outlook will stop working if Microsoft enforces this

Automate the audit

Microsoft provides a license utilization report in the admin center under Reports > Usage. This shows which services each user actually uses (Exchange, OneDrive, Teams, Office apps) and helps identify users whose license tier does not match their behavior.

Common mistakes

Removing the license before converting the mailbox. This starts the 30-day deletion timer. If you forget to convert within 30 days, the mailbox data is permanently lost. Always convert to a shared mailbox first, then remove the license.

Not copying OneDrive files before removal. OneDrive files are user-scoped, not shared. When the license goes and the grace period expires, those files are gone. Copy anything important to SharePoint or another user’s OneDrive before removing the license.

Forgetting about Microsoft 365 Group ownership. If the user owned Groups or Teams, those become ownerless when the account is deleted. Ownerless Teams still function but nobody can add members, change settings, or manage channels. Check Group ownership before removing the account.

Not checking for litigation or compliance holds. If the user’s mailbox is on hold for legal reasons, removing the license does not delete the data, but it does make the mailbox harder to access. Work with your legal or compliance team before touching licenses on accounts with active holds.

Paying for annual licenses and not using them. If you purchased annual licenses and employees leave mid-year, the licenses are paid for regardless. You cannot get a refund for unused months on annual billing. However, you can reassign the license to a new employee immediately. Keep your available license count visible and reassign promptly when someone leaves.

How Sequentur handles license management

License management is part of our managed Microsoft 365 services. When an employee leaves, we handle the full offboarding workflow including mailbox conversion, OneDrive file preservation, Group ownership transfer, and license removal. When a new employee joins, we assign the appropriate license tier based on their role and configure their account with the correct security policies from day one.

We run quarterly license audits for every client to identify unused seats, mismatched plan tiers, and opportunities to right-size. For most tenants, this audit identifies savings that exceed the cost of the management service.

If you suspect your tenant has unused licenses or you are not sure what happens to data when you make changes, reach out through our contact page and we can review your current state.