There's just something about the sign-off. The absence of an e-mail closing, even if it's from someone you know well, makes the message seem cold and abrupt. A thoughtful ending, however, whether it's polite and professional or a clever conclusion from a friend, can verify the tone of the e-mail and set the stage for future correspondence. Letitia Baldrige, the manners expert, told the New York Times that sign-offs are especially important because, "We need grace in our lives, and I'm not talking about heavenly grace. I'm talking about human grace. We should try and be warm and friendly."
I believe most of us would agree with Ms. Baldrige in that there should be an affable or at least respectable energy in all of our exchanges. In any e-mail event, there comes the moment of truth when you arrive at the bottom of the electronic missive and think How the heck do I end this? Here are a few suggestions for different circumstances:
• Professional Sign-Offs: It's better to err on the side of being too formal than too casual, especially if you're writing to a superior or a new client for the first time. E-mail is such a breezy way to communicate that we often forget that we still have to convey reverence for those we work with and those we hope to work with. In the case of the first three or four e-mail exchanges with a colleague or client, I would take it to the formal max with Sincerely, Cordially, Warmest Regards, or Sincere regards. After a few messages have gone back and forth, provided you feel comfortable, you can end with something along the lines of Yours, Yours truly, Best, Warmly, or Cheers.
A quick word on "Cheers": I know this is a pet peeve of many who believe those of us who aren't British shouldn't be employing this word. I agreed wholeheartedly, until I realized how convenient "Cheers" is when ending an e-mail. It's perky and professional in one quick word. I would never say the word "cheers" aloud (except when clinking wine glasses with someone), but as far as e-mail is concerned, I think we Americans can borrow it.
• Between Friends: There are different levels of friendship--some are good friends and others casual acquaintances. I'll include a sign-off, no matter which type of friend I'm writing, if I haven't written them in a while. I'll only forgo the sign-off if we've gone back and forth a handful of times, but even then I usually try to sign at least my name. An e-mail that's empty at the end somehow doesn't seem right. Whimsical endings such as Take care, Thanks again, Lots of love, and Chat soon, are all acceptable--thought I would only use Chat soon, if you do plan on calling or seeing the person in the near future. XOX is a standard, fun, and admittedly girlie, way to sign-off. Once again, I think Cheers (the universal ending) can be borrowed from the professional word and used here, as can Yours, and Yours truly. I wouldn't, however, say Best, or Regards, to a friend. Those two words can be interpreted as very distant and curt outside of the corporate arena.
• When in Romance: In the early days of dating e-mail sign-offs can be very telling and, believe it or not, enjoyable. It's fun to insert your personality into sign-offs. I dated a man last year, and the two of us had a blast with the e-mail endings. The first time he wrote he ended with Smacks. I'm still not sure what that means. Is he giving me a high-five? Is he smacking me on the butt? But it somehow seemed very appropriate and very him. Some of his other closings were: Giddy up, Getting excited, and Talk to you soon gorgeous. Some of mine to him were: Enjoy your evening, and Happy first full day of spring handsome. One time, I even went so far as to say, Can't think of a clever exit, yours was too cute. He and I got into a light disagreement once, and I wrote him a semi-confessional e-mail and ended it Honestly, Samara. He responded in semi-apologetic mode and ended it Hopefully, John. I dated another man years ago and recall him ending one of his virtual notes with Stay warm. This was in the middle of the first cold front of the year, and I found his closing to be considerate and right on cue.
Putting thought into your closing when you're dating someone or wanting to date them leads that person to believe you put a great deal of thought into them too. Don't stress too much over the perfect sign-off though--you can start by ending e-mails the same way you'd end them with friends until you're very comfortable. I'd say the rule to live by here is to be yourself, and end the e-mails in whatever way continues the tone of the overall message and also makes you feel at ease. If you can't be yourself with this person over e-mail then there's not much hope of being yourself around them otherwise.