From Office for PC
1. In any Office app, go to File > Account (or Office Account in Outlook) > Sign out.
2. Close all Office apps.
From Office for Mac
1. In any Office app, select the name of the Office app in the top menu.
2. Select Sign Out.
3. Quit out of all Office apps.
From Office on iOS (iPhone/ iPad)
1. In any Office app, tap Account > tap the account you're using.
2. Tap Sign Out > Sign Out again to confirm.
3. Close all Office apps.
For Office on Android or Chromebooks:
1. In any Office app, from the Recent screen, tap the person icon.
2. Tap your name (don't tap View Profile).
3. Tap Sign Out > Sign Out again to confirm.
4. Close all Office apps.
From the Office Portal
1. Go to https://portal.office.com/account/
2. Choose Apps & Devices
3. Under "Office apps & devices" select View apps & devices
4. Click the arrow for the dropdown menu next to "DEVICES"
5. This will display all of the devices that you are currently signed into office on. Click Sign Out on any devices that you don't recognize (this will free up a license).
It can take up to 72 hours for Office to detect that you've signed out.