This article explains how to add BCC recipients to an email using Yahoo Mail in a web browser.
Using Yahoo Mail: CC and BCC
BCC stands for blind carbon copy. In the context of an email, a person who is BCC'd sees the message, but no other recipients see their name. You can use the BCC feature to send emails to multiple people without them knowing who else is receiving the message.
You can blindly email two or more contacts at once using the BCC feature in your Yahoo Mail account.
Sign in to your Yahoo Mail account and select the Compose button in the top left corner to open a new email message window.
