It's easy to think of email sign-offs as a bit stodgy. An unnecessary throw-back to the times when writing and delivering a letter was a lot more involved and effort intensive than just dashing off a quick reply in your inbox. Quaint, but probably something you can skip. Heck, in some circles, it might even be considered cool to end your emails on an aloof note.

Slightly old fashion as they may seem though, email sign-offs are still important. Emails might be a quick and disposable means of communication, but they're still communication. As humans, we have all kinds of built-in expectations, heuristics, and preferences when it comes to communication, and in particular, how other people address us. You wouldn't just turn and walk away from a person without saying anything in a face-to-face conversation (unless you were actively trying to burn a bridge), so why do we assume that it's okay, or even fashionable, to do the same in an email?

There are a lot more subtleties involved in a good email than just the subject line and content, especially if you're trying to build a business relationship with the recipient. The way you sign-off says something about you and your business, so make sure it's communicating the right ideas.

A big problem with sign-offs is that they are hard to do well. When used carelessly, they can either seem robotic and insincere, or cloying and amateurish. That why I'm typically skeptical of email signatures that include stock phrases. You should take the extra second to tailor your sign-off to the email you've sent. But how do you know what's appropriate? There is no concrete answer, you need to use your best judgment and empathy. But there are a few basic routes to take.

If you're contacting a professional relationship, whether it be a client, a contractor, or a business collaborator, it's best to err on the side of formality. In these cases, simple and respectful are the watch words. You don't want to labor the point and overdo it, but you don't want to appear flippant either.

"Regards” is a simple, direct, and respectful way to close an email. It's kind of the vanilla scoop of closers though, reliable and inoffensive, but not particularly thrilling either. Depending on the situation and your relationship with the recipient, you may want to try a variation such as "best regards,” or "kind regards” to warm up the tone a bit. 

"Sincerely” is definitely one of those older phrases that can seem a little out of step in today's business world, but it still has a place. This can be useful if your email seems a little too flattering and you're worried it appears like you're just trying to butter someone up. Conversely, it's also a good way to end difficult emails where you've had to hash out a dispute or disagreement. It's the sign-off equivalent of "let's figure this out together,” acknowledging that there is a problem, but still seeking an amiable resolution.

If you regularly exchange emails with a particular recipient, closing each mail with something as formal as "sincerely” seems anything but. There is no need to stand on ceremony if you have a strong working relationship with another person and regularly correspond with them several times a week. 

When a quick "thanks!” or "much appreciated” is all you need, that's all you should use. Building familiarity and ease with your correspondence conversation isn't something to avoid, it's something to embrace. Your business professor isn't going to spring out of the shadows and rap you on the knuckles for closing an email on a familiar tone. Remember, tailor your messages to suit the relationship, don't let your relationship be informed by your messages.

When emailing prospective customers or business contacts in a way where any of the classics seem a little stuffy, it's a good idea to try some positive, relationship building language.

End your emails on a optimistic note with something like "talk to you soon” or "hope this helps.” A message that implies an eagerness to hear back from the recipient. That said, always make sure your sign-off matches the tone of you and your business. You want to enter a professional arrangement with this person, not swap emoji-snap chats and fail videos. It can be a tricky line to walk, so make sure you're always applying some thought to how your message will be received before you click that send button.

Go nuts. End your emails with nicknames, "peace,” "hit me back,” whatever makes you and your peers smile. Yeah sure, the main point of a sign-off like this is to have a good time, but a relaxed sign off can also serve a greater purpose – building unity and camaraderie among your core group.

When people spend all day with their nose to the grindstone, fending off emails from clients, shippers, agencies, and more, a little levity in the inbox can go a long way. Again, the sign-off should be tailored to the person you're talking to, not awkwardly shoved some pap line you write out of reflex.