An attention letter is a type of business letter with an attention line. In simple terms, you add an extra line to your letter stating who the letter is for.The Letter of Reference State Bar of Nevada ATTN: form is 1 page long and contains: 0 signatures; 0 check-boxes; 10 other fields. Country of origin: OTHERS The Attention Line is placed above the Recipient Line, that is, above the name of the firm to which the mailpiece is directed. Download a proof of residency letter template for family members, notarized or non-notarized, tailored for legal use. Know what attention lines in business letter is and how to place them effectively. Read more to know about the same to leverage benefits.