An employee leaves: which licence keeps their mailbox and Microsoft OneDrive?

The options

• 

  Keep the current licence

  Microsoft 365 E5

  CHF 54.33

  Microsoft list price for Switzerland, excl. VAT, as of 4 October 2026 [1]

  Includes

  • Nothing changes: mailbox and Microsoft OneDrive stay as they are, so there is nothing to restore later [2]
  • Includes Microsoft 365 retention policies, so the mailbox can be kept as an inactive mailbox when the account is deleted [3]

  Limits

  • –Blocking sign-in doesn’t stop the cost: you pay until you unassign the licence and reduce the licence count [2]

  SPE_E5
• 

  A smaller licence for the mailbox

  Exchange Online (Plan 2)

  CHF 6.50

  Microsoft list price for Switzerland, excl. VAT, as of 4 October 2026 [4]

  Includes

  • 100 GB mailbox [5]
  • Archiving included [6]
  • Lets you put a hold on the mailbox before the account is deleted, so it becomes an inactive mailbox [2]

  Limits

  • –Contains Microsoft Exchange Online only: no Microsoft OneDrive and no Office apps [7]
  • –Only needed until the account is deleted; after that the licence is free for a new user [8]

  EXCHANGEENTERPRISE
• 

  Add-on for a hold

  Exchange Online Archiving for Exchange Online

  CHF 2.40

  Microsoft list price for Switzerland, excl. VAT, as of 4 October 2026 [9]

  Includes

  • Adds archiving, In-Place Hold and Litigation Hold [6]
  • Added to Exchange Online (Plan 1), it allows the same hold before deletion as Plan 2 [2]

  Limits

  • –Not needed with Microsoft 365 Business Premium, E3 or E5, Office 365 E3 or E5, or Exchange Online (Plan 2): they already include archiving [6]

  Requires

  • →Exchange Online (Plan 1), Microsoft 365 Business Basic or Microsoft 365 Business Standard [6]

  EXCHANGEARCHIVE_ADDON
• 

  A smaller licence for Microsoft OneDrive

  OneDrive for Business (Plan 1)

  Microsoft doesn’t publish a Swiss price for this licence. IT partners can quote it.

  Includes

  • Keeps the Microsoft OneDrive licensed, so it isn’t set to read-only on day 60 or archived on day 93 [10]

  Limits

  • –Microsoft OneDrive is designed for an individual’s own work files. Departmental data belongs in Microsoft SharePoint, and a per-user licence may not be assigned to a department or other non-human entity [11]

  WACONEDRIVESTANDARD
• No licence up to 50 GB

  Shared mailbox

  No licence needed up to 50 GB [12]

  Includes

  • Mail and calendar stay, and colleagues you give access to can work in it [13]
  • Microsoft calls it a less expensive way: no licence while the mailbox is smaller than 50 GB [14]
  • Can be converted back to a user mailbox later [13]

  Limits

  • –Over 50 GB it needs Exchange Online (Plan 2), which allows up to 100 GB [13]
  • –A Litigation Hold or In-Place Hold needs Exchange Online (Plan 2), or Plan 1 with Exchange Online Archiving [13]
  • –Don’t delete the user account: it anchors the shared mailbox [13]
  • –Without a password reset, the old username and password keep working on the shared mailbox [13]
  • –Inbox rules are kept after the conversion [13]
  • –Everyone who opens it needs their own Microsoft Exchange Online licence [12]
  • –Mail and calendar only: the Microsoft OneDrive still turns read-only on day 60 [10]

  Requires

  • →The mailbox must still have its licence when you convert it; remove the licence afterwards [13]
• No licence after deletion

  Inactive mailbox

  No licence needed [3]

  Includes

  • Microsoft’s way to retain a former employee’s email: apply a retention policy, confirm it is applied, then delete the account [15]
  • Kept for as long as the retention policy says: months, years or indefinitely [15]
  • Microsoft Teams chats covered by a Microsoft Teams retention policy are kept with it: they are stored in the mailbox [16]
  • Authorised people search and export it with Content Search (eDiscovery) [8]

  Limits

  • –Can’t receive email and isn’t shown in the address book [8]
  • –Keeps the mailbox only: the Microsoft OneDrive follows its own deletion process [17]
  • –Getting it back takes work: recover it as a new mailbox with Microsoft Exchange Online PowerShell and license it, or copy its contents into an existing mailbox [18]
  • –With an auto-expanding archive it can’t be recovered or restored, only searched and exported [18]
  • –Don’t change the user name (UPN) or primary email address before deleting the account [15]

  Requires

  • →A retention policy or hold before the account is deleted, which Microsoft 365 E3 and E5, Microsoft 365 Business Premium, Office 365 E3 and E5, Exchange Online (Plan 2) or Exchange Online Archiving provide [3]
• 

  Pay-as-you-go backup

  Microsoft 365 Backup

  Pay-as-you-go: billed for the data backed up, not per user; restores are free [19]

  Includes

  • Backs up Exchange mailboxes, Microsoft OneDrive accounts and Microsoft SharePoint sites [19]
  • Recovery window set per backup policy: 3 months, 6 months, 1 year or 2 years [19]
  • After a user is deleted, their mailbox and Microsoft OneDrive backups are kept for one year from when each backup was made [20]
  • Also offered through partners’ backup applications built on Microsoft 365 Backup Storage, paid through the partner [19]

  Limits

  • –A deleted user’s Microsoft OneDrive comes back “orphaned” and has to be reconnected to a user [20]
  • –A deleted user’s mailbox comes back through the inactive mailbox recovery (PowerShell); within 30 days of the deletion, restore the user first [20]

Key differences

1. 1To retain a former employee’s email, Microsoft recommends a Microsoft 365 retention policy applied before the account is deleted. The mailbox then becomes an inactive mailbox [15]
2. 2To keep a former employee’s email and calendar at hand for colleagues, Microsoft’s route is converting the mailbox to a shared mailbox [14]
3. 3Remove the licence and the mailbox is kept for 30 days. Add the licence back within that time and it is fully active again; after that it is deleted and can’t be recovered [21]
4. 4Once a mailbox has no licence, eDiscovery tools such as Content Search can no longer search it [21]
5. 5An unlicensed Microsoft OneDrive whose user still exists turns read-only on day 60 and is archived on day 93. From then on, neither admins nor users can open its content until an admin licenses, reactivates or moves it [10]
6. 6The simplest restore is re-licensing a user who still exists: an archived Microsoft OneDrive is reactivated within 24 to 48 hours, with no reactivation fee [10]
7. 7Microsoft OneDrive’s deletion process starts only when the user account is deleted. Blocking sign-in or removing the licence doesn’t start it [17]
8. 8After 12 months unpaid, Microsoft OneDrive data might be deleted regardless of retention policies, eDiscovery and holds [17]
9. 9Removing the licence frees the user’s phone number for calls in Microsoft Teams, so it can go to someone else [2]
10. 10Under Microsoft’s licence terms, a leaver’s licence can go to a new user for the rest of its term. Moving a licence for a short time (within 90 days of its last assignment) is allowed only to cover an absence [22]
11. 11Swiss law requires the accounting records and accounting vouchers, together with the annual report and the audit report, to be kept for ten years from the end of the financial year. The annual report and the audit report are kept on paper and signed; the accounting records and vouchers may also be kept electronically if they stay linked to the underlying transactions and can be made readable at any time (Code of Obligations, Art. 958f). Not every email or file is an accounting record or voucher; this is general information, not legal advice [23]

What to do, and when

1. Last working day

   Reset the password, sign the user out of all sessions and block sign-in. Blocking on its own can take up to 24 hours. [24]

2. Last working day

   Wipe or block the former employee’s mobile devices. [25]

3. While the licence is still assigned

   If colleagues need the mail, convert the mailbox to a shared mailbox now. The option only appears while the mailbox still has its licence. [13]

4. Before deleting the account

   For compliance, put a retention policy on the mailbox and confirm it is applied. No hold, no inactive mailbox. [15]

5. Then

   Delete the user account with the hold in place; that frees the licence too. Don’t remove the licence first: Microsoft asks for all holds to be removed before a licence is removed. [2]

6. Days 1 to 30

   A mailbox whose licence was removed is kept for 30 days, and adding the licence back restores it. After that it is gone. [21]

7. Days 60 and 93

   An unlicensed Microsoft OneDrive turns read-only on day 60 and is archived on day 93. Move what the team needs to Microsoft SharePoint before then. [10]

8. After the account is deleted

   The manager, or a secondary owner, gets access to the Microsoft OneDrive for 30 days by default (adjustable in the Microsoft SharePoint admin center). It then spends 93 days in the recycle bin. [17]

Who it’s for

• A successor needs the mail for a few weeks: convert it to a shared mailbox (under 50 GB), reset the password, block sign-in, then remove the licence. Copy the Microsoft OneDrive files the team needs to Microsoft SharePoint before day 60.
• Email must be kept for compliance: put a retention policy on the mailbox (Microsoft 365 E3, E5 and Business Premium include one; otherwise use Exchange Online (Plan 2) or the archiving add-on), confirm it is applied, then delete the user. The inactive mailbox needs no licence.
• Files must stay: move them to Microsoft SharePoint, set a longer Microsoft OneDrive retention for deleted users, or keep a OneDrive licence for a short while.
• You want an undo for mistakes or ransomware: Microsoft 365 Backup or a third-party backup. Restoring a deleted user means PowerShell and reconnecting the Microsoft OneDrive; re-licensing a user who still exists is far simpler.
• Shared mailbox or inactive mailbox: Microsoft offers the shared mailbox to keep mail at hand for colleagues, and recommends the inactive mailbox for retaining a former employee’s email.
• Not needed: months of Microsoft 365 E5 on a blocked account “just in case”. A retention policy, a shared mailbox or a short-term smaller licence keeps the mail and files for less.

ClearSource’s reading of Microsoft’s documentation — not a recommendation for your situation.

What changed recently

1. 1 July 2026

   Unlicensed Microsoft OneDrive accounts that stay unpaid count towards a cumulative 365-day non-payment clock and can be deleted once it runs out. For accounts already unpaid on 1 July 2026, that is not before 1 July 2027 [10]