What Blind Carbon Copy Does in Email and When to Use It

Blind carbon copy (BCC) hides the addresses of everyone you send a message to from each other

Blind carbon copy, or BCC, is an email field that lets you send a message to multiple people without showing them who else received it. When you put someone's address in the BCC field, that person gets the email, but their address does not appear in the message header — not to the main recipient, not to anyone on the regular CC line, and not to anyone else on the BCC line. Each BCC recipient sees only their own address and the sender's address.

The difference between CC and BCC matters because CC (carbon copy) shows everyone on the message who else got it. BCC keeps that information private. If you send an email to alice@company.com and CC bob@company.com, Alice can see that Bob got the message. If you BCC Bob instead, Alice will never know Bob received it.

Most email services — Gmail, Outlook, Yahoo Mail, and others — include a BCC field in the compose window. You may need to click "Show fields" or a similar option to see it, because BCC is hidden by default in many interfaces.

Key Takeaways

• BCC recipients receive the email but their addresses remain invisible to all other recipients, including the main recipient and other BCC recipients.
• CC shows all recipients who else got the message; BCC hides that information entirely.
• The BCC field is usually hidden in email compose windows and must be revealed before you can use it.
• BCC is useful for protecting privacy when sending to many people, but some workplaces have policies about when it is appropriate to use.

When to use BCC instead of CC

Use BCC when you want to send the same message to multiple people but those people do not need to know who else received it. A common example is a newsletter or announcement sent to a large group. If you send a company-wide update to 50 employees using BCC, each person receives the message but cannot see the other 49 addresses. This protects everyone's email address from being visible to coworkers they may not know.

BCC is also useful when you want to keep someone informed without making it obvious to the main recipient. For example, if you email a client with a question and want your manager to see the exchange, you can BCC your manager. The client will not know your manager is reading along. However, be aware that some workplaces discourage this practice because it can feel deceptive — the client may reasonably expect to know who is reading their messages.

Another practical use is protecting your own privacy. If you are sending an email to a group of people who do not know each other and should not have each other's contact information, BCC ensures no one accidentally gets a list of email addresses they did not ask for.

How to find and use the BCC field

In Gmail, open a new message and look for "BCC" next to the "To" and "CC" fields at the top. If you do not see it, click the down arrow or "Show trimmed content" option. Once you click BCC, a text box appears where you can type or paste email addresses, just like the To and CC fields.

In Outlook (both web and desktop), the BCC field appears by default in the compose window on the right side. If it is not visible, click the "BCC" button in the ribbon or message options.

In Yahoo Mail, click "BCC" in the compose window to reveal the field. In Apple Mail on Mac or iPhone, BCC is usually visible in the compose window, but you may need to enable it in settings.

Once you have entered addresses in the BCC field, send the message as you normally would. The email goes out to everyone — To, CC, and BCC recipients — but only the To and CC recipients can see who else got the message.

What BCC recipients can and cannot see

A BCC recipient sees the message content, the sender's name and address, and the addresses of anyone in the To and CC fields. They do not see other BCC recipients' addresses, and they do not see that they themselves were BCC'd — the message looks like a regular email to them.

The main recipient (in the To field) and anyone on the CC line can see each other's addresses but cannot see any BCC addresses. If you put someone in To and someone else in BCC, the person in To will never know the BCC person received the message.

This is different from forwarding, where the original recipient can see that you sent the message to someone else. With BCC, there is no trace that the BCC recipient ever received it.

Privacy and workplace considerations

BCC is a legitimate email feature, but using it to secretly monitor someone's communications can damage trust. Many workplaces have policies about when BCC is appropriate. Some organizations discourage BCC entirely because it can be used to hide information from people who should know they are being monitored.

If you work in a regulated industry — law, finance, healthcare — your organization may have specific rules about BCC use. Some companies require that all business emails be transparent, meaning BCC is not allowed. Others permit it only in specific situations, like sending newsletters or protecting privacy in large group messages.

When in doubt, ask your manager or check your company's email policy. Using BCC to secretly copy a supervisor on a client conversation, for example, might be allowed in your workplace or might be considered a breach of trust. The feature itself is neutral; how you use it matters.

BCC versus other email privacy options

If you want to send a message to many people without showing addresses, BCC is the standard method. However, some email services offer alternatives. Gmail's "Confidential Mode" lets you set an expiration date on messages and prevent recipients from forwarding or copying text, though this does not hide recipient addresses from each other.

If you need to send sensitive information to a group, some organizations use mailing lists or distribution groups instead of BCC. A mailing list is a single email address that automatically forwards messages to multiple people. The sender addresses the list, not individual people, so individual addresses stay hidden. This is common for newsletters and department-wide announcements.

For truly sensitive communications, some workplaces use encrypted email or secure portals instead of regular email. These options provide more control over who sees what and when, but they require setup and are not built into standard email services.

Common mistakes with BCC

The most common mistake is forgetting that BCC recipients cannot see each other. If you BCC five people and expect them to know they are part of a group conversation, they will be confused when they receive a message with no context about who else is involved. If you need people to know they are part of a group, use CC instead.

Another mistake is assuming BCC is completely invisible. While BCC addresses do not appear in the message header that recipients see, a determined person could potentially discover that they were BCC'd by checking email headers or by asking the sender. BCC is private, not secret — it just prevents casual discovery.

Some people also accidentally put the same address in both To and BCC, which means that person receives the message twice. Most email services will warn you if you do this, but it is worth double-checking before you send.

Frequently Asked Questions

Can someone tell if they were BCC'd on an email?

Not from the message itself. A BCC recipient sees a normal email with no indication they were BCC'd. However, if they check the full email headers (an advanced feature in most email clients), they might see evidence. In practice, most people never look at headers, so BCC remains private for casual use.

If I BCC someone, can they reply to the whole group?

No. A BCC recipient can reply to the sender or to the To and CC recipients if they choose, but they cannot reply to a group that includes other BCC recipients, because they do not know who those people are. If you need group conversation, use CC instead.

Is it legal to BCC someone without their knowledge?

In most places, yes — BCC is a standard email feature. However, some workplaces have policies against it, and in certain contexts (like recording someone without consent), it could raise legal or ethical issues. Check your organization's email policy and use BCC responsibly.

What happens if I BCC someone on a reply to an existing conversation?

The BCC recipient receives only that one reply, not the entire conversation history. They see the message you sent but not previous emails in the thread. If you want them to have context, you may need to forward the earlier messages separately or use CC instead.

Can I use BCC to send the same message to many people at once?

Yes, that is one of the main uses of BCC. Put all the addresses in the BCC field, leave the To field blank or put your own address there, and send. Each person receives the message but cannot see the other recipients' addresses. This is how many newsletters and announcements are sent.