123, X Street, Y Avenue
[Subject: Normally bold, summarizes the intention of the letter] -Optional-
Dear Austin Parker,
Everyone here at Junk Clothing would like to offer our deepest sympathies upon the death of Craig, your firm’s co-founder. We have had a long working relationship with Craig and yourself, and it has been a good five years. Craig did much to aid our own business and he will be sorely missed by everyone.