Who This Affects and What It Fixes
This guide is for Microsoft 365 administrators at small businesses who need to prevent a specific user from appearing in the Outlook Global Address List (GAL). Hiding the user removes them from the shared address book while keeping their mailbox fully active—they can still send and receive email as normal.
Before You Start
You will need admin access to the Microsoft 365 Admin Center. No software needs to be installed to use the Admin Center method. Keep in mind that once saved, the change can take up to 60 minutes to appear—and in some cases up to 24 to 48 hours—across all Outlook clients.
Steps to Hide a User from the GAL
- Go to https://admin.microsoft.com and sign in with your admin account.
- In the left-hand menu, navigate to Users > Active users.
- Search for and select the user you want to hide from the GAL.
- In the user settings panel, select the Mail section.
- Click Manage email apps or Mail settings, then open the Exchange settings. This may redirect you to the Exchange Admin Center.
- In the Exchange Admin Center, go to Recipients > Mailboxes.
- Select the user’s mailbox and click Edit.
- Under General, locate the Manage global address list visibility option.
- Uncheck Show in my organization address list.
- Click Save.
What Happens After You Save
The user’s mailbox remains active. They can continue to send and receive emails without interruption. Their name simply will not appear when other users browse or search the organization’s address book in Outlook.
If your organization uses Outlook in cached mode, some users may still see the hidden address until their Offline Address Book (OAB) is updated. They can manually refresh the OAB in Outlook to reflect the change sooner.
Need Help?
If you run into trouble or do not have admin access to make this change, contact the ACS support team and we can take care of it for you.
Common questions
Does hiding a user from the GAL delete or disable their mailbox?
No. Hiding a user from the Global Address List does not delete or disable the mailbox. The user will continue to send and receive emails as usual—they simply will not appear in the organization’s shared address book.
How long does it take for the GAL change to take effect in Outlook?
Changes typically propagate within up to 60 minutes, but in some cases it can take 24 to 48 hours for the update to appear across all Outlook clients. Users running Outlook in cached mode can manually update their Offline Address Book (OAB) to see the change sooner.
Can a hidden user still receive emails sent directly to their address?
Yes. Hiding a user from the GAL only removes them from the visible address list. Anyone who already knows the user’s email address can still send mail to them, and the user can still reply and send messages normally.