In Mac OS X Mail, this is easy, of course. Mailing a list of people in one go is no more difficult than sending an email to a single recipient. Whether a group is manually constructed or of the "smart" type does not matter.
Send a Message to a Group Fast in Mac OS X Mail
To send a message to all members of an address book group in Mac OS X Mail:
- Create a new message.
- Type your email address in the To: field.
- You can try skipping this step and leave the To: field empty. Some mail servers may reject your thus incomplete message, however.
- Make sure the Bcc: field is visible.
- Type the name of the desired address book group in the Bcc: field.
- Of course, you can also drag-and-drop the group from either the Address Book application or the Mac OS X Mail Addresses panel (Window | Address Panel in the menu).
- Compose and send your message.
Larger Groups
Note that most mail servers will reject messages that have too many — often over 50 or maybe 25 — recipients.
For mailing larger groups easily, you can use a group mailing service.

