Customizable Recipient Limits in Office 365 Exchange Online

Office 365 tenant admins can now customize the Recipient Limits setting from 1 to 1000. Admins can make changes either via Remote PowerShell (RPS) or via the Exchange Admin Center (EAC). The full complement of customization capabilities is available via RPS, while a sub-set of those are available in the Exchange Admin Center.

Update a single mailbox

Set-Mailbox -RecipientLimits 20

Update multiple mailboxes

(Get-Mailbox | where {$_.RecipientTypeDetails -ne "DiscoveryMailbox"}) | % {Set-Mailbox $_.Identity -RecipientLimits 10}

Update the default for new mailboxes created in the future (all plans)

Get-MailboxPlan | Set-MailboxPlan -RecipientLimits 50

Verify the changes by running:

Get-Mailbox -Identity "" | Select RecipientLimits

Change the recipient limit for your organization by running:

Set-TransportConfig -MaxRecipientEnvelopeLimit <NumberOfRecipients>