Font Size: The traditional font size for a professional letter is 12. The font should be Times New Roman or Arial. However, if you are using letterhead, the letterhead may be in different font size and style. Font Style: There is no need to use different styles within a professional letter. Use a uniform font (book print font such as Times New Roman or Arial) and avoid underlining, italicizing, or bolding. However, if you are using letterhead, the letterhead may be in a different font style.
Return address and date: (Upper right hand corner) Once upon a time, this was necessary in case the letter became separated from the envelope, but I doubt that happens much any more. Even so, this is where your reader is going to look to find your address and the date the letter was written, so it should be there. Mailing address of recipient: (Left_hand side, one line below the return address) This identifies the recipient of the letter. In office environments, letters are often removed from their envelopes and circulated; this helps the letter get back to its rightful recipient.