In this article, we discuss how to include a reason in your resignation letter and provide some samples to guide your writing. Reason for Resignation.(Resignation Notice). An employee wishing to leave in good standing shall file a written resignation with the appointing authority in the form of a Resignation Notice or a letter. These top samples of resignation letters for personal reasons can be used as helpful templates when you are looking to resign due to personal circumstances. If additional entries are necessary please use a separate sheet prepared in the same format and select the "upload" button. California State University, San Bernardino.