Salutation: (Two lines below the recipient’s address, or about 1Ǚ down the page) The person the letter is intended for. Avoid “Dear Sir/Madam” and especially “To Whom it May Concern” unless absolutely necessary; not directing a letter to an exact recipient suggests that you don’t care who reads it (or you would have made a call or checked their website) _ and may prevent the letter from reaching someone who can act on your letter.
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 Don't let the slightly archaic feel of a formal business letter tempt you into using flowery, outdated language.