Thx. TY. Thanks. Thanks! How are you supposed to sign off from a professional email? A few lawyers shared good pointers with ABA Journal. Here’s a quick breakdown:

Are you asking for a favor? If so, go ahead and use “thank you” or “thanks.” But there is a difference. The authors argue that “thank you” comes off as more earnest while “thanks” can come off either as more confident or cold, depending on the favor you’re asking. For the most part, do not use “thanks in advance.”

Consider your purpose: And that purpose, in almost every situation, should be to make the reader of your email feel good. 

Know how your recipient signs off on emails: This especially helps when you have a tough email to send. Using the same sign off they do likely gives the least risky chance of offending them.   

Check out the full article for examples of good and bad email sign off etiquette.