SOLVED: How Much Space Your Email Taking in Office365?

If you have an Office365 account, you likely know that you have 50GB worth of storage space.  However, it is not obvious how much of that 50GB limit you are currently using.  Questions like: ‘How large is all of my email’, ‘How much space do I have left in my Office365 email?’ and ‘What is my mailbox usage on Office365?’ need answers.

There are four ready ways to determine the size of the mailbox in Office365:

OUTLOOK ESTIMATE:

You could look at the size of the mailbox you have in Outlook and use that as a pretty solid gauge of how much did you are using.

1. Open Outlook
2. Click FILE > INFO
3. Note the size listed under MAIL BOX SETTINGS, or
   Click TOOLS > MAILBOX CLEANUP > VIEW MAILBOX SIZE

USER INFORMATION:

1. Log into mail.office365.com  in your browser
2. Click the SETTINGS cog (top right corner)
3. Click MAIL
4. Expand GENERAL > MY ACCOUNT
5. Note the size listed in MAILBOX USAGE

ADMINISTRATOR PORTAL:

If you are an Administrator Office365, you can see each users mailbox size by:

1. Log into portal.office365.com in your browser
2. Expand USERS > ACTIVE USERS
3. Click in a username
4. In the frame that opens on the right side, expand MAIL
5. Click EDIT EXCHANGE PROPERTIES
6. Click MAILBOX USAGE

ADMINISTRATOR POWERSHELL COMMAND:

If you are an Administrator Office365, you can see each users mailbox size using the following PowerShell command which I borrowed from THIS post.

Function Connect-ExchangeOnline {

$office365Credential = Get-Credential

$global:office365= New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://ps.outlook.com/powershell/ -Credential $office365Credential  -Authentication Basic   –AllowRedirection

Import-PSSession $office365

}

Get-Mailbox | Get-MailboxStatistics | Select-Object DisplayName, IsArchiveMailbox, ItemCount, TotalItemSize | Format-Table –autosize

OR

Get-Mailbox | Get-MailboxStatistics | Select-Object DisplayName, IsArchiveMailbox, ItemCount, TotalItemSize | Export-CSV –Path “C:\Logs\ExchangeOnlineUsage.csv”

If you are wondering how it was so easy to fill up your 50GB, it is because Office365 now allows attachments up to a MASSIVE 150MB per message.  This might sound like a great idea but most email systems you are sending to will block messages larger than 10MB or 15MB and it will also be difficult to find and work on files that you have in Exchange, because it is not a file system… it is an email system and with very few exceptions you should use it that way.