Information Security Awareness, Training and Motivation — Native Intelligence, Inc.

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When to Use the Bcc Field in Email

Have you ever received an email that was forwarded to you with a joke, motivational story, cartoon, or warning about a hoax?

Look at an email message that has been forwarded many times and count the number of email addresses you can see for people you do not know.

Most email software lets you send email several ways:

  • Using the "To" or "Cc" fields, so that everyone can see everybody else's email address
  • Using the "Bcc" field, so that everyone can't see everybody else's email address

The "Bcc" field gets its name from "Blind Carbon Copy." Years ago, "Bcc" was used to indicate a carbon copy that was made but not acknowledged (the addressee didn't know about it).

What's the Difference Between Using the Cc and the Bcc fields?

When you use the "Bcc" field, a copy of the message goes to every email address you add to the "Bcc" field.

The difference between this and the "Cc" field is that neither the "Bcc" field itself nor the email addresses in it appear in any of the copies (and not in the message sent to the person in the "To" field either).

The only recipient address that will be visible to all recipients is the one in the "To" field.

For the most anonymity, put your own address in the "To" field and use "Bcc" for all the other recipients.

When You Send a Message to More Than One Person

Use the "Bcc" field to hide email addresses so that you don't disclose the recipients' email addresses to all the other people to whom you are sending the message or to spam email address harvesters. 

This is important because when you don't hide the email addresses, those addresses can get forwarded around the Internet. 

For example, when you send ten of your friends an email showing all ten email addresses, and those people forward that email to ten of their friends, 100 people now have your friends' email addresses.

This is one of the ways that your email address can get on a spammer's list.

Here's a suggested reply to ...

... someone who includes your email address in the "To" field of a message sent to a small (or large) circle of friends

Dear (insert sender's name here),

I just got your email message.

Would you do me a favor? When you send email to a group of people, and I'm one of the group, would you make sure that you put my email address in the "Bcc:" field and not in the "To:" or "Cc:" fields?

(Insert instructions from the links at the bottom of this page if you know which email program the person uses). Here's an example using Outlook:

To add Bcc: Recipients in Outlook

  • Go to the Options ribbon.
  • Make sure Show Bcc is clicked.
  • Use the "Bcc..." field like the To... and Cc... fields.

Here's an example of what this looks like using Outlook:

Screen shot from Outlook showing the BCC field

This reduces the amount of junk email (spam) that I receive and helps protect my privacy.

Spammers use email address harvesting programs that scan email messages sent via the Internet. These programs look for email messages that are sent to multiple recipients.

When you use the "Bcc" field to send email, these spam address collectors will not be able to view the address and add it to their databases of valid email addresses.

When you include all the recipients' addresses in the To field, you share each person's address with everyone else on the "To" list.  As this message gets forwarded, some people will include the previous message, and then my address (along with everyone else's) will be sent out with more and more other names, making it an even more likely target for spammers.

Use the "To" or "Cc" fields only when you want each of the recipients to know who else you sent the message to. If that's not necessary, it's better to protect everyone by putting their addresses in the "Bcc" field.

Thank you.

(Insert Your Name)


Off site link

There is an excellent article by Heinz Tschabitscher that contains specific step-by-step instructions on how to add BCC recipients in a variety of email programs:

To go directly to the steps for your email program:


arrow Would you handle this a different way?

Let us know!

Article by K Rudolph, CISSP © Native Intelligence, Inc.  All rights reserved.
Updated: November 26, 2007 (after one too many chain letters from well-meaning friends)