Checking the storage quota (mailbox size) of your (Microsoft 365) account using Outlook on the Web

Your Exchange mailbox has a finite storage quota (100 GB for faculty and staff). It's good practice to monitor your quota and delete unnecessary email messages to keep your mailbox well below quota.

  1. Log in to your Microsoft 365 account at
  2. In the top right corner click the gear icon, then at the bottom click View all Outlook settings.
  3. From the left pane, select General > Storage.

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

Keywords:email mail space data storage full webmail OWA Exchange O365 M365   Doc ID:62204
Owner:TSS Tier 2 .Group:Northwestern
Created:2016-03-24 16:22 CDTUpdated:2020-12-14 12:14 CDT
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