Managing the quota (mailbox size) of your (Exchange) account using Outlook Web App (OWA)

Your Exchange mailbox has a finite storage quota (25GB for faculty and staff). It's good practice to monitor your quota and delete unnecessary email messages to keep your mailbox well below quota.

Check quota usage

  1. From the top-right corner click the gear icon, then click Options.
  2. Click Mailbox Usage.
    Here is an image that shows the location of the Mailbox Usage bar. It is located in the My Account window below the account information and above the Settings for POP or IMAP access link.

Reduce size of mailbox

  1. Log in to the Outlook Web Application (OWA) at
  2. Click Inbox on the left side of the page to display the contents of your Inbox.
  3. Click the Items By <Criteria> drop-down above the list of messages, then select Size in the drop-down list that appears. Make sure Largest on top is selected for Order to show you the messages that will gain you the most space if you delete them; set Conversations to On and wait for message list to load.
  4. Delete old or unneeded messages.
  5. Click the Junk E-mail folder and repeat steps 3 and 4.
  6. Right-click the Deleted Items folder and select Empty Folder.

For additional assistance please contact the IT Support Center at 847-491-4357 (1-HELP), via chat at or via email at

Keywords:email mail space data storage full   Doc ID:62204
Owner:TSS Tier 2 .Group:Northwestern
Created:2016-03-24 16:22 CDTUpdated:2019-02-04 11:59 CDT
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