How To Write A Grievance Letter To Your Boss . To, the manager, department of human resources, i am writing this letter to complain formally against my boss, mr. In the first paragraph, you should give hr some idea why you are writing to them. Grievance letter to your employer Grievance template from www.rocketlawyer.co.uk The first step in doing so is to write to your employer. Thank the person to whom the letter is addressed in the first paragraph, showing that you're at least a little bit grateful for the opportunity to work with the company. In the second paragraph, provide the details of the salary issue.