Have you ever encountered these common mistakes when sending business emails?

“I forgot to CC someone!”

“I sent a mass email using CC instead of BCC…”

While we use these address fields every day, a small oversight can lead to serious consequences, such as a personal data breach.

Correctly managing your recipients is not just about efficient communication—it is also a reflection of your professional etiquette and your ability to handle information with care.

In this article, we will go back to the basics and provide a clear guide on the roles and etiquette of To, CC, and BCC.

This article is for those who:

  • Review To, CC, and BCC etiquette.
  • Write professional, trustworthy emails.
  • Learn Japanese business email basics.

\Japanese business etiquette/
「日本で働くためのビジネス基礎講座きそこうざ

Email Risks: A Small Slip, a Big Loss

You might think, “It’s just a wrong address,” but in the business world, this can become a major error that damages your professional credibility.

Risk of Data Breaches

A common but critical mistake is using CC instead of BCC.

For example, imagine sending a company announcement to 30 clients who do not know each other.

If you put their addresses in the CC field, every recipient can see everyone else’s name and email address.

This is a serious “personal data breach.”

We occasionally see this in the news, and it is a perfect example of how a small oversight can escalate into a major crisis.

This is not just a personal error; it becomes a corporate-wide issue with legal and financial implications.

Once trust is broken, regaining it takes a very long time.

Proper Recipient Management

Failing to set the correct recipients can lead to confusion and frustration for those receiving your emails.

【Putting everyone in the “To” field】

When everyone is addressed in the “To” field, it becomes unclear who is responsible for taking action. This often results in a situation where no one takes ownership or replies.

【Leaving key people out of the “CC” field】

 If managers or stakeholders are not kept in the loop, they cannot track project progress. This may lead others to perceive you as someone who lacks basic “Ho-Ren-So” (Report, Contact, and Consult) skills.

In today’s busy workplace, some people find it overwhelming to receive too many CC emails. You don’t need to CC your boss on every single thread. Instead, aim to be selective and only include them in conversations that are truly relevant to them.

The Roles of To, CC, and BCC

To communicate effectively, it is essential to understand the specific role of each field and how to use them correctly.

  • To: The Primary Recipient(s) These are the main people the email is addressed to. They are expected to take action or provide a reply.
  • CC (Carbon Copy): For Information Sharing Recipients in this field are not the primary target of the email but need to be kept “in the loop.” While they should stay informed, they are generally not expected to take immediate action.
  • BCC (Blind Carbon Copy): For Confidential Sharing or Mass Mailing Use this when you want to share the content with someone without the other recipients knowing. It is also the standard for “mass emails” (like newsletters) to recipients who do not know each other.
Field Primary Purpose Action Required? Visible to others?
To Primary action Yes Yes
CC Awareness/FYI No Yes
BCC Privacy/Mass mail No No

CC Etiquette

Let’s take a look at the etiquette for CC recipients.

Should I list CC recipients?

The reason is to clearly inform the primary recipient (To) that the information is also being shared with others.

By listing the CC recipients at the beginning, the primary recipient will understand:

“Since (Name) is also reading this, I need to provide a professional and timely reply.”

“I don’t need to send a separate report to (Name) later because they are already in the loop.”

When including CC recipients in the salutation, you can write it like this:

株式会社かぶしきがいしゃメイルン 佐藤様さとうさま

 (CC:営業部長えいぎょうぶちょう 田中様たなかさま

いつもお世話せわになっております。

If the CC list is long, listing every name can make the salutation look cluttered. In such cases, it is perfectly acceptable to omit the names or use a collective term like (CC:関係者各位かんけいしゃかくい).

Using “Reply All”

If someone is included in the CC field, make it a rule to use “Reply All” to include everyone in your response.

The sender included those people because they need to stay informed. Therefore, you should avoid removing anyone from the thread based on your own judgment. Doing so can break the flow of information.

If you accidentally reply only to the “To” recipient, don’t worry.

Simply resend the email with the CC recipients included, and add “[Resend]” to the beginning of the subject line to clarify.

Sample Opening Lines for Resending an Email with CC Recipients

件名: 再送さいそう○○のについて

(Toの方の名前)様

世話せわになっております。(自分の名前)です。

申し訳ございません。先ほどのメールにてCCの方々かたがたふくめずに返信してしまいましたため、あらためて全員に共有させていただきます。

※内容は先ほどお送りしたものと同様どうようです。

—(以下、先ほどの返信内容)—

Always check if anyone is CC’d before hitting reply.

Adding or removing recipients

As an email thread progresses, you may find it necessary to change who is included in the CC field.

In such cases, the professional approach is to include a brief note about the change.

  • When removing someone from CC: 「〇〇さんは、別部署べつぶしょ異動いどうになったため、今後こんごはCCからはずさせていただきます。」 → Conveying that you are not “excluding” them.
  • When adding someone to CC:本件ほんけん、担当の〇〇さんもCCにくわえさせていただきます。」 → Suddenly adding someone unfamiliar to the CC list can catch the recipient off guard.

When to reply from CC

Generally, it is the responsibility of the “To” recipient to respond, so those in CC are not expected to take action.

However, there are exceptions—such as when the primary recipient is out of the office or when the person in CC has more specific information.

In these cases, it is courteous to include a brief opening note to explain why you are stepping in.

「CCから失礼しつれいいたします。
本日ほんじつ○○(Toの人ひと)が不在ふざいのため、わって返信へんしんいたします。」

BCC Etiquette

Next, let’s take a look at the proper etiquette for using BCC.

Privacy in mass emails

Why must you use BCC instead of CC when emailing multiple people who don’t know each other?

  • Protecting Privacy: When you use CC, every recipient can see the email addresses of everyone else on the list. If they are not already acquainted, this is considered a leak of personal information.
  • Courtesy to Recipients: It is important to respect people’s privacy; most people do not want their contact information shared with someone they have never met.
Mailun
Mailun
To avoid mixing up CC and BCC, always double-check your recipient list one last time before hitting “Send”!

BCC recipients should not reply

As mentioned earlier, BCC allows you to send an email without the “To” or “CC” recipients knowing.

A sender uses BCC when they want to share information with someone discreetly.

If a BCC recipient replies to the thread, the “To” and “CC” recipients will be confused and wonder, “Who is this?” or “Why was this person secretly included?”

Since BCC recipients can see everyone on the list, it’s easy to hit “reply” without thinking.

However, as a general rule, you should never reply if you are in the BCC field.

If a response is absolutely necessary, make sure to reply only to the original sender (the “To” person) privately.

Conclusion

Properly using To, CC, and BCC is more than just etiquette; it is an essential skill for respecting people’s time and protecting sensitive information.

Before you hit “Send,” take a moment to double-check these three points:

  • Is it clear who needs to respond?
  • Is everyone who needs the information included? Are there any unnecessary recipients?
  • If it’s a mass email, are the addresses hidden in the BCC field?
Mailun
Mailun
It might feel a bit tricky at first, but just keep the recipient’s perspective in mind when choosing your fields!

Every small, thoughtful action you take builds the foundation of your professional credibility.

To help you overcome these challenges, mailun-lab offers specialized learning materials for Japanese business email writing.

メイルン
メイルン
Perfect for mastering Japanese emails!

[What You’ll Achieve]

  1. Draft & edit faster
  2. Communicate with confidence
  3. Build lasting trust.

Check NOW

If you found this helpful, feel free to explore our other articles below:

Business Japanese Email Materials by Former HR & Teacher | mailun-lab
”Business Japanese Email Materials" by Former HR & Teacher | mailun-labStruggling with Japanese business emails? Perfect for JLPT N3+ learners, our materials created by an ex-HR expert cover not just phrases, but the cultural logic behind them. Improve your professional skills with our self-study guides. Subscribe today for a free "Basics" textbook!...

\ Join & Get a Free Gift! /

Get your free copy of “Business Japanese Email – Basics” by joining our newsletter!

What’s inside:
*Free Guide (PDF)*
*Discount coupons*
*Pro etiquette tips*

Subscribe