Anything that you'd use in an informal communication is inappropriate for a business letter. This includes slang, text_speak, emojis, and anything off_color or casual. If you're used to communicating mostly with friends, family, or even co_workers you've worked with for a long time, an appropriate closing for a business letter will probably feel pretty stilted at first. Don't worry about it – your colleague or business associate won't feel that way when he or she reads your correspondence. What seems unnatural to you will feel respectful and polite to the recipient.
The Complimentary Close: It is a humble way of ending a letter. It is written in accordance with the salutation. The most generally used complimentary close are Yours faithfully, Yours sincerely, and Thanks & Regards. Signature and Writer’s Identification: It includes signature, name, and designation of the sender. It can also include other details like contact number, address etc. The signature is handwritten just above the name of the sender. Enclosures: Enclosures show the documents attached to the letter. The documents can be anything like cheque, draft, bills, receipts, invoices etc. It is listed one by one. Copy Circulation: It is needed when the copies of the letter are sent to other persons. It is denoted as C.C. PostScript: The sender can mention it when he wants to add something other than the message in the body of the letter. It is written as P.S.