My thoughts on email etiquette fall into two categories:
1. Email guidelines - I keep these in mind when I'm composing an email, but they are somewhat open to interpretation based on personal preference.
2. Email blunders - these turn my stomach every time I see them. Avoid these blunders if you want to maintain professional relationships and/or be taken seriously.
I'll separate my discussion into these two categories, and I'll cover these topics over a few posts. Keep in mind that while you can apply this advice to casual email correspondence, the main application is for professional correspondence.
Email Guideline #1:
Think About Your "To," "Cc," and "Bcc" Lines
Think critically about who you are sending this email to, and which line they should be listed on in the recipients section of the email.
People in the "To" line should be actively engaged in the conversation. If you are expecting a response from somebody, or think they may potentially provide a response to your email, include them in the "To" line. Similarly, if you are responding directly to somebody's email, they should be in the "To" line.
The "Cc" line is for the people that should be privy to the conversation, but from whom you don't necessarily expect a reply. The "Cc" line is useful if you think the conversation may involve somebody in the future and you want them to follow along with the email thread from the beginning. The line to tread here is between (a) annoying somebody with an extra email and (b) annoying somebody when they are expected to contribute to a thread they weren't originally privy to, and now must decipher the entirety of the conversation in order to see why they are being included. Often, the "Cc" line is also used to include proxies for those in the "To" line - for instance, you may include people in the same department, the supervisors, or the direct reports of those in the "To" line.
The "Bcc" line has two main uses:
The first use is sending an email to a large group of recipients when one or more of the following is true: (a) you don't want them to know who else you sent the email to, (b) you don't want the recipients to have the contact information for the others on the email, and (c) you want to discourage a large thread of "Reply-All" responses.
The second "Bcc" use is surreptitiously sending a copy of the email to another person when you don't want the "To" or "Cc" line recipients to be aware that this other person received the email. BEWARE THIS USE! - if the person in the "Bcc" replies to all, the other recipients on the email will become aware that you included this person in the "Bcc" line, and that you were "secretly" passing this information on to them. If you think there is any chance the person you are secretly including in "Bcc" may "reply to all," I would suggest simply forwarding them a copy of the information instead.
Whether you are the originator of the email thread, or merely replying to somebody else's thread, you should consider the recipients. If you are replying, think twice before removing people from the thread. The original sender may have had a specific reason for including them. Alternatively, however, if there is somebody crucial missing from the conversation, add them in the "To" or "Cc" line, and consider adding a direct appeal to them in the body of the email (ie, "Hi Tom, You may have the most information on this - please take a look at the question Betty sent over. Thanks, Mark"). You may also re-organize the "To" and "Cc" lines if you are replying, and you feel there is a brazen error (Aside: If it is a small correction between the "To" and "Cc" lines, consider foregoing your re-organization so long as all the critical parties are included in either the "To" or "Cc." Depending on how much attention the sender pays to their email (hopefully a lot), they may take umbrage at your re-organization, or consider it passive aggressive if you continually adjust their recipients line. If they are repeat offenders though, definitely clue them in to their mistake... and then send them my way for a refresher!).
If you take care to consider your email audience you'll receive the information you need faster, you'll keep your team on the same page, and you'll avoid the embarrassing mistake of including somebody you didn't mean to include, or excluding somebody you didn't mean to exclude.
I would suggest filling in the recipients line before you start writing your email, and then taking a second look just before you hit the send button.
I'll cover more email guidelines, and blunders in following posts, but if you have comments, questions, or personal stories, feel free to share in the comment section below!
UPDATE: Part 2 in this series has also been posted. You can find it here.