Do graduate schools care if letters are confidential or not? In general, graduate programs prefer confidential letters. Admissions officials say that it displays more confidence on the part of the applicant if letters are "confidential" (meaning you, the applicant cannot see the letter). The Letter Service is required to indicate on the letter if it is confidential or non-confidential.
Use standard formal letter writing conventions to begin. A letter of recommendation is like any other professional communication, and follows the same general rules and guidelines. Place your address on the top right, followed by the date—spelled out. Below that, on the left, place the recipient’s name (if known) and address. Open the letter with a formal business greeting. Ex: Dear Ms. Smith, Dear Sir or Madam, (if you don’t know the recipient’s name)