The twelfth tape is to Bryce Walker, a boy who had sexually assaulted Hannah in a hot tub at the party. Later in that tape Hannah begins to explain how she plans on killing herself.
The final and last tape is addressed to Mr. Porter, a teacher who filled in as a guidance counselor. Hannah went to him with her feelings of depression and feeling alone and he did nothing to help her. The book ends with clay feeling different, and confronts a girl names Skye who he sees behaving just like Hannah did and has potentially prevented another teen from committing suicide.