When you're writing a business letter or sending an email message, it's important to close your letter in a professional manner. The ideal ending for a business letter conveys your thanks and respect, without eccentricity or an overly familiar tone. Although it may seem old_fashioned, most business professionals expect written correspondence – whether via a letter or an email – to be written and formatted in a conservative manner.
Formal communication is on the wane in modern life, but there are still times when it's the only correct way to reinforce a connection or convey information. If you're applying for a job, looking for a recommendation, or expanding your network, err on the side of formality. Don't let the slightly archaic feel of a formal business letter tempt you into using flowery, outdated language.