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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).

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. 

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 e-mail address can get on a spammer's list.

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

You could try sending them a reply like this one:

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 field?

Screen shot showing the BCC field in an email program

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 thier 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 field 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)

 

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)

You are here:  Home > Articles > When to Use the BCC Field