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How Does Using BCC Help Reduce Spam?


Is it true that if I use BCC to email attachments, it will mean less danger of spam? How’s that?

It’s not so much about attachments as it is any email that you receive and then forward.

And it’s not so much about saving yourself from getting more spam, but saving the people that sent you the email you’re about to forward.

It’s all about keeping their email addresses private and un-harvestable.

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The scenario works like this: you get a wonderful piece of humor via email – maybe a joke, some goofy pictures, or something else that you want to forward to your friends. (Note: Never forward anything that actually asks you to forward it without checking it out first. It’s likely an urban legend.)

The mail that you got looks something like this:

Subject: This is funny

I thought this joke was kinda funny:

A pirate walked into a bar and the bartender said, ...

(All the email addresses are fake and just for example purposes.)

Your friend has emailed you some humor and cc’d a number of other people.

… never forward anything that actually asks you to forward it …

Think about that for a moment. You can see all the email addresses on the CC line. If you’re a spammer, you just got five more known-valid email addresses that you can add to your list of email addresses to spam. In fact, any of the people on the CC line could do this as well.

But it gets worse. You think this joke is really funny and worth forwarding on to more of your friends, so you hit Forward and create a message that looks like this:

Subject: FW: This is funny

Pretty cute...

> From:
> To:
> Cc:,,
> Subject: This is funny
> I thought this joke was kinda funny:
> A pirate walked into a bar and the bartender said, ...

Just look at all the email addresses that are visible to anyone who gets this message. It’s a veritable gold mine of known-good email addresses that they can then use for any purpose they wish. Spam, of course, is the most obvious, but there are a raft of privacy issues that result as well.

And after the message has been forwarded a few times, the list of juicy email addresses at the top often exceeds the length of the actual message at the bottom!

(And you’d be surprised at how often the resulting email messages gets forwarded by someone to a mailing list that is archived on the web where it a) lives pretty much forever and b) is even more easily harvested by spammers.)

Stop!There are two things you must do to avoid adding to the problem:

  • Use BCC for the recipients. This will prevent the email addresses that you send the humor to from being visible to the people that get it. (How you do this will vary from mail program to mail program, but almost all have it.)
  • Edit out any email addresses in the body of the message before you send. This will remove all the prior recipients from being visible and has the added benefit of making the email easier to read.

Of course, you should always consider whether the message should be forwarded at all, but I’ll assume you’ve made that decision properly.

So this time when we forward that original, we do those two things:

  1. Instead of entering all those addresses on the TO or CC lines, we send the message “to” ourselves and put all the recipients on the BCC line.
  2. After pressing the Forward button, but before pressing Send, click in the body of the message and simply delete all the lines that are nothing more than forwarded email headers.

Using the example from above, here’s the result:

Subject: FW: This is funny

Pretty cute...

> I thought this joke was kinda funny:
> A pirate walked into a bar and the bartender said, ...

What the people getting this message see is this:

Subject: FW: This is funny

Pretty cute...

> I thought this joke was kinda funny:
> A pirate walked into a bar and the bartender said, ...

Not an email address to be found.

Nothing for spammers to harvest.

24 comments on “How Does Using BCC Help Reduce Spam?”

  1. And if any e-mail says “forward this to everyone you know,” don’t.

    BTW, sending chain mail is a violation of the terms of service of almost every ISP and web-mail service. If you get caught, you could lose your e-mail account.

  2. i have been telling people this for years. i am going to forward this page to all those people today. your explanation is concise and to the point with easy to understand why and how to. thanks!

    If you do it in one mailing, be sure to … BCC them. 🙂

    – Leo
  3. You are absolutely right about the collection of addresses that come with many forwarded mails,
    but there is not even any need to fill in the To:line nor the CC line all addresses on the blind copy line will do,using Outlook Express.So no need even to send it to your self.

    That’s actually not true for all mail programs and all mail providers. Some will reject mail without a visible recipient, so it’s just easier to send it to yourself. Also email without a visible recipient, when it does make it through, is more likely to be flagged as spam.

    – Leo
  4. It’s certainly the conventional wisdom these days that you should use BCC when sending to multiple recipients, but to play devil’s advocate for a moment I’d like to point out that there are drawbacks. For instance, you sent several people an important e-mail, but can’t remember whether you left certain addressees out. It’s easy to reopen it in your sent folder and check, isn’t it?

    Not if you BCCed them! You won’t see the blind copied recipients even in Outlook Express; I’ve tried, even using dodges found on the net which apparently worked in the past, but not now, at least on my system. So you’d better keep a list of those addressees somewhere else. Then I have to admit that there have been times when someone else has lifted my address from a list on a message, or I have found an acquaintance’s in that way, and the resulting communications have been helpful. Everyone is so jealous of their privacy nowadays that finding people can be difficult, eg with most telephone numbers beung ex-directory. I am not convinced that the gains from this outweigh the losses.

    I am also not convinced that spammers harvest their addresses in this way. It doesn’t sound very practical. I have been sending and receiving e-mails with large numbers of addresses for years with no noticeable affect on my spam: I think the servers are quite good at filtering it now. So I think the question is arguable.

  5. Not only should you remove the lines that are nothing more than forwarded email headers, the message would be much more readable were you to remove all of the > symbols.

    In outlook express if you click on Tools, then Options, then the Send tab, uncheck the box ‘Indent message on Reply’ for both HTML settings and Text settings.

    If, however, you use web mail, some web mail programs do not allow you to make any changes to the message being forwarded but send them as attachments after adding the indents and headers. (One more reason to use an POP e-mail instead of web mail.)

  6. While the BCC addresses are definitely not included in the copies of the message sent by your email provider to the BCC addressees, they appear to be included in the original message as it travels from you to your email provider; that would seem to be necessary so that your email provider knows where to send the copies. So a spammer could still harvest the BCC addresses if your email is intercepted on the way from you to your email provider, although not on its way from there to the recipients.

  7. Great tip…just goes to show….you can learn somethin new everyday, no matter how much you think you know…lol Of course I never forward anything, it’s like a petpeeve to me.

  8. Much easier way to do this. I just copy the the message and paste it in a new e mail with only the address’s I want….to, CC or BCC

  9. @ Bernard Winchester,
    Yes, its harder to mfind who you BCC’d, but its possible. (In Outlook Express)
    Find the email in ‘Sent Items’
    Then click on the ‘Details’ tab. They are all there easy to find.

    Always use BCC is you send to multiple people unless you want them to know you have sent it to each other.

  10. It doesn’t seem to work this way if you use AOL..
    I have told people how to send to Bcc, but if they have AOL, they can’t do it!

  11. In windows live mail you can see who you sent it to by just looking in sent items and I leave the ‘to’ empty most of the time and they have always went where I sent them to none have been refused and all were answered when I requested them to be.

  12. Yes, Marion Sutton, it does work on AOL. I am on AOL and use BCC and it works. In the “Copy To:” section, type in all your recipients, putting them all together in parentheses. That is, put the open parentheses before the first e-mail address and the close parentheses after the last one. I use this method all the time.

  13. For serious purposes, i.e. business, a proprietary e-mail program like MS Outlook is infinitely preferable to Outlook Express. The former also enables you to see to whom you blind copied so that you can easily keep track.



  15. It would really help with the bcc. I use it all the time but deleting all the addresses are a pain as they have usually been sent to upteen people before I get to them.I still delete them before I send them on.I even sent explaining how to use bcc but it is easier just to send it. Thank you for addressing this subject

  16. All the big email services (Gmail, Yahoo) claim to be opposed to spam, why don’t they just make BCC the default setting and require personal attention when you want to send an open (visible) carbon copy?

  17. Many thank yous for this article. I seem to have a fair number of tech “challenged” friends & family. This forwarding of cutesy jokes, riddles, etc. always comes with the above mentioned CC problems. I try to get them to visualize crossing out the address on an envelope then remailing it to other recipients.

    Anyhow, your explanation is much better. Oh, also to “Digital Artist” love the suggestion of BCC as the default setting.

  18. Please use the full words when sending how to information like what is CC and BCC I don’t have any idear what they mean please explane them.Thank you.

  19. BCC is a great tool…but for the stuff yakked about in this article…Better yet! Stop sending all this junk around the Internet. Do you really really think this behavior means you’re the friend of someone because you load up their chuckle box? It bogs down email servers, slows the Internet with extra traffic, and sometimes has inadvertently passed links to virus sites. If you or your friends need chuckles that bad, figure out how to be funny on your own. MOST of the seriously needed information sent around the net is garbage, untrue, and ridiculous. And the little that is true and worthwhile…if it’s so worthwhile, bring it to the attention of an agency responsible in that area and see to it they publish it for people to see. CHECK THINGS OUT THOROUGHLY BEFORE YOU SEND ANYTHING AROUND! Just because you poked over to Snopes and see an approval flag does not necessarily mean you read the fine print there, or researched further. Many of the “true” ones are also BS or otherwise unworthy of your attention. (chuckle on that)
    And btw…don’t use Forward. Copy paste the message body into a new email, then call up your mailing list into the BCC field. If there is none, put each email address inside parentheses.

  20. There is another problem that your suggestions seems to bring up. BCC can also be used to hide your address in such a manner that you’ll get spam and never see your address in it?

    Your explanation of BCC here is the first instance I’ve actually seen in 15 years that managed to possibly explain this to me.

    Email may be a pain sometimes but I would think IM is 10X the pain. Since any protocol involves giving up control at some point to deliver data you are at the mercy of the network at all times I would suppose. The system was born open and people are used to getting their messages etc without a hassle and somebody will get what they want eventually. Perhaps if BCC were mandatory for all addresses beyond the first?

    Still, when you get a spam email that has no trace of you in it it’s probably worse to you than the other way around, highly bothersome and doesn’t leave you feeling any better, as in, “how the blank…”?

  21. I wonder how the spammers have the time to look at the millions of email each day and harvest email addresses. I don’t see how that is possible.

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