When you know the recipient’s name, sign it “Sincerely yours” or just “Sincerely”, or in the US “Yours truly” is acceptable. Don’t try anything more cutesy or friendly unless a) you know the recipient quite well and are certain you can be informal without seeming disrespectful, or b) you have a “trademark” letter ending that’s part of your public persona (and the talent and popularity to pull it off). Signature and printed name: Signing your name is a minimal assurance that you stand behind what was written.
The Best Formatting for a Business Letter. A business letter is a formal document often sent from one company to another or from a company to its clients, employees, and stakeholders, for example. Business letters are used for professional correspondence between individuals, as well. Although email has taken over as the most common form of correspondence, printed out business letters are still used for many important, serious types of correspondence, including reference letters, employment verification, job offers, and more.