The ones I use most often in my business emails: -Best Regards, -Regards, Common ones I see other people using: -Warm Regards, -Warmest Regards, -Respectfully, -Sincerely,

In British English a very formal letter or e-mail could start and end as follows: "Dear Mr Smith [...] Yours sincerely" However it is fairly unusual for an e-mail to be so formal. This might be more appropriate for a letter sent as a PDF attachment to an e-mail, rather than in the body of the e-mail itself. In American English I believe the equivalent ending is "Yours truly". But I'm British, not American. Normally when send e-mails I end them with "Kind regards" when writing to someone I don't know very well, or "All the best" when writing to someone I know reasonably well (as a colleague).

Other ideas: Best wishes, Sincerely, Many thanks,

All examples with a comma after the word(s). I usually use "Regards". You can also use "Best regards", "Warm regards", "Kind regards", "Yours truly", "Sincerely", "Yours sincerely". More casual are "Best wishes", "Many thanks" and so on. Hope this helps! :)

You could say best wishes, yours truly, kind regards till we meet again many ways for saying bye in a letter what will intimately decide how you say goodbye would be the content of your letter is it a formal letter or a casual letter. To whom you writing to plays a major role.