Mailbox plans in Exchange Online

A mailbox plan is a template that automatically configures mailbox properties in Exchange Online. Mailbox plans correspond to Microsoft 365 and Office 365 license types. When you assign a license to a new user, the corresponding mailbox plan is used to configure the settings on the new mailbox that's created. If you change the license that's assigned to an existing user, the settings in the mailbox plan that's associated with the new license are applied to the user's existing mailbox.

The following table describes the mailbox plans that you're likely to see in Exchange Online.

Subscription or license Mailbox plan display name
Exchange Online Kiosk

Microsoft 365 or Office 365 Enterprise F3

ExchangeOnlineDeskless
Microsoft 365 Business Basic

Microsoft 365 or Office 365 Enterprise E1

Exchange Online Plan 1

ExchangeOnline
Microsoft 365 or Office 365 Enterprise E3

Microsoft 365 or Office 365 Enterprise E5

Exchange Online Plan 2

ExchangeOnlineEnterprise

Notes:

  • The availability of a mailbox plan in your organization is determined by your selection when you enroll in Microsoft 365 or Office 365. A subscription might contain multiple mailbox plans. A mailbox plan might not be available to you based on your subscription or the age of your organization.
  • The name value of the mailbox plan is appended with -<GUID> (for example, ExchangeOnlineEnterprise-44107b46-a8c4-4573-a7ba-bb004fde4d58).

For every mailbox plan (returned by the Get-MailboxPlan cmdlet), there's a corresponding Client Access services (CAS) mailbox plan (returned by the Get-CasMailboxPlan cmdlet). The names and display names of the mailbox plans and CAS mailbox plans are identical, and the relationship between them is unbreakable (both the mailbox plan and the corresponding CAS mailbox plan are assigned to the mailbox when you license the user; you can't assign just the mailbox plan or just the CAS mailbox plan separately).

The modifiable settings that are available in mailbox plans by using the Set-MailboxPlan cmdlet are described in the following table:

Setting Default value Description
IssueWarningQuota Varies by license. The user receives a warning message when their mailbox reaches the specified size.

For more information, see Capacity alerts.

MaxReceiveSize Varies by license. The maximum total message size that can be received by the mailbox. This value is roughly 33% larger than the actual message size to account for Base64 encoding.

For more information, see Exchange Online limits.

MaxSendSize Varies by license. The maximum total message size that can be sent from the mailbox. This value is roughly 33% larger than the actual message size to account for Base64 encoding.

For more information, see Exchange Online limits.

ProhibitSendQuota Varies by license. The user receives a warning message and they can't send messages when their mailbox reaches the specified size (which must be greater than the IssueWarningQuota value).

For more information, see Capacity alerts.

ProhibitSendReceiveQuota Varies by license. The user receives a warning message and they can't send or receive messages when their mailbox reaches the specified size (which must be greater than the ProhibitSendQuota value).

For more information, see Capacity alerts.

RetainDeletedItemsFor 14.00:00:00 (14 days) Depending on your subscription, you can change this value up to 30 days. For more information, see Change how long permanently deleted items are kept for an Exchange Online mailbox.
RetentionPolicy Default MRM Policy Note: The value for this property must either be null (blank) or match the name of the Exchange retention policy that is configured as default for the tenant otherwise the experience may be inconsistent when creating new mailboxes, enabling disabled mailboxes, and changing licenses.

If a mailbox is assigned an Exchange retention policy that is not default, the RetentionPolicy value of the mailbox will be overwritten when changing licenses and will need to be manually reset to the original value.

For more information about retention policies, see Retention tags and retention policies in Exchange Online.

RoleAssignmentPolicy Default Role Assignment Policy Grants users permissions to their own mailbox and distribution groups. For more information, see Permissions in Exchange Online.

The modifiable settings that are available in CAS mailbox plans by using the Set-CasMailboxPlan cmdlet are described in the following table:

Setting Default value Description
ActiveSyncEnabled True Enables or disables Exchange ActiveSync (EAS) access to the mailbox.
ImapEnabled Varies by license. Enables or disables IMAP4 access to the mailbox.
OwaMailboxPolicy OwaMailboxPolicy-Default Configures the user's settings in Outlook on the web (formerly known as Outlook Web App). For more information about Outlook on the web mailbox policies, see Outlook on the web mailbox policies in Exchange Online.
PopEnabled True Enables or disables POP3 access to the mailbox.

Modifying the settings of a mailbox plan won't update the settings of an existing mailbox that already has the mailbox plan applied. To modify these settings on an existing mailbox, you can:

  • Modify the corresponding mailbox settings directly in the Exchange admin center (EAC) or in Exchange Online PowerShell (the Set-Mailbox and Set-CasMailbox cmdlets).
  • Assign a different license to the user. The mailbox plan that corresponds to the new license will be applied to the existing mailbox (the settings in the mailbox plan will be applied to the existing mailbox).

What do you need to know before you begin?

  • Estimated time to complete each procedure: 2 minutes.

  • You need to be assigned permissions before you can perform this procedure or procedures. To see what permissions you need, see the "Mailbox settings" entry in the Feature permissions in Exchange Online topic.

  • You can only use Exchange Online PowerShell to perform the procedures in this topic. To connect to Exchange Online PowerShell, see Connect to Exchange Online PowerShell.

Tip

Having problems? Ask for help in the Exchange Online forum.

Use Exchange Online PowerShell to view mailbox plans

These examples return a summary list of all mailbox plans:

Get-MailboxPlan | Format-Table Name,DisplayName
Get-CasMailboxPlan | Format-Table Name,DisplayName

These examples return the modifiable property values in all mailbox plans:

Get-MailboxPlan | Format-List DisplayName,IsDefault,Max*Size,IssueWarningQuota,Prohibit*Quota,RetainDeletedItemsFor,RetentionPolicy,RoleAssignmentPolicy
Get-CasMailboxPlan | Format-List DisplayName,ActiveSyncEnabled,ImapEnabled,PopEnabled,OwaMailboxPolicy

These examples return detailed information for the mailbox plan named ExchangeOnlineEnterprise.

Get-MailboxPlan -Identity ExchangeOnlineEnterprise | Format-List
Get-CasMailboxPlan -Identity ExchangeOnlineEnterprise | Format-List

This example returns the mailbox plan that's assigned to the user named Suk-Jae Yoo.

Get-Mailbox -Identity "Suk-Jae Yoo" | Format-List MailboxPlan

To return all mailboxes that had a specific mailbox plan applied, do the following steps:

  1. Run the following command to find the distinguished name of the mailbox plan:

    Get-MailboxPlan | Format-List DisplayName,DistinguishedName
    
  2. Use the following syntax to return the mailboxes that have the mailbox plan assigned:

    Get-Mailbox -ResultSize unlimited -Filter "MailboxPlan -eq '<MailboxPlanDistinguishedName>'"
    

    This example returns the mailboxes that have the ExchangeOnline mailbox plan applied.

    Get-Mailbox -ResultSize unlimited -Filter "MailboxPlan -eq 'CN=ExchangeOnline-93f46670-2ae7-4591-baa4-ee153e090945,OU=constoso.onmicrosoft.com,OU=Microsoft Exchange Hosted Organizations,DC=NAMPR22B009,DC=PROD,DC=OUTLOOK,DC=COM'"
    

For detailed syntax and parameter information, see Get-MailboxPlan and Get-CasMailboxPlan.

Use Exchange Online PowerShell to specify the default mailbox plan

The default mailbox plan is used as the default template for new user mailboxes that you create without a license (because the license specifies the mailbox plan). For shared mailboxes, and resource mailboxes without a license, the ExchangeOnline mailbox plan is assigned, regardless of the default. For more information, see Exchange Online limits.

To specify the default mailbox plan, use the following syntax:

Set-MailboxPlan -Identity <MailboxPlanIdentity> -IsDefault

This example specifies the ExchangeOnline mailbox plan as the default.

Set-MailboxPlan -Identity ExchangeOnline -IsDefault

For detailed syntax and parameter information, see Set-MailboxPlan.

Use Exchange Online PowerShell to modify mailbox plans

To modify a mailbox plan, use the following syntax:

Set-MailboxPlan -Identity <MailboxPlanIdentity> [-MaxReceiveSize <Size>] [-MaxSendSize <Size>] [-IssueWarningQuota <Size>] [-ProhibitSendQuota <Size>] [-ProhibitSendReceiveQuota <Size>] [-RetainDeletedItemsFor <TimeSpan>] [-RetentionPolicy <RetentionPolicyIdentity>] [-RoleAssignmentPolicy <RoleAssignmentPolicyIdentity>]
Set-CASMailboxPlan -Identity <MailboxPlanIdentity> [-ActiveSyncEnabled <$true | $false>] [-ImapEnabled <$true | $false>] [-PopEnabled <$true | $false>] [-OwaMailboxPolicy <PolicyIdentity>]

This example modifies the mailbox plan named ExchangeOnlineEnterprise to use the retention policy named Contoso Retention Policy.

Set-MailboxPlan -Identity -RetentionPolicy "Contoso Retention Policy"

This example disables Exchange ActiveSync, POP3, and IMAP4 access to mailboxes in all CAS mailbox plans.

Get-CASMailboxPlan | Set-CASMailboxPlan -ActiveSyncEnabled $false -ImapEnabled $false -PopEnabled $false

For detailed syntax and parameter information, see Set-MailboxPlan and Set-CasMailboxPlan.