You can hide recipient names and addresses in your email messages by using Bcc, which stands for "blind carbon copy." Bcc helps you keep people in the loop and respect their privacy by not disclosing their identities. When you send an email message, your recipients can see the addresses in the To and Cc fields, but not the Bcc field.
For example, if you send a message to Cheryl and Chester and add James to the Bcc field, Cheryl and Chester will not know that James also received a copy of the message. If Cheryl uses Reply All to respond to the message, James will not be included in the reply.
Note: The Bcc field isn't currently available for meeting requests. If this is a feature you would like to see, visit the Outlook Suggestion Boxto leave your feedback. The Outlook team is actively monitoring this forum.
Find and add a recipient to the Bcc field
If you don't see the Bcc box under the Cc box when composing your email, select the Options menu at the top of a new email message, and then select Bcc from the Show Fields group.
If you're replying to a message in the reading pane and want to show the Bcc box, select the Bcc button at the top of the screen in the Show Fields group.
Type the recipient's name or email address in the Bcc field.
Note: The Bcc field isn't currently available for meeting requests. If this is a feature you would like to see, visit the Outlook Suggestion Box to leave your feedback. The Outlook team is actively monitoring this forum.