You don't even need to give a reason. You can simply write, "Please accept this letter as my resignation.Without going into too much detail, explain the reasons for leaving. I regret to inform you that, after much thought, I have decided to resign. Please accept this letter as a formal notice of my resignation. Professional resignation letter examples for different reasons. Free templates and writing guide to resign on a positive note without feeling awkward. It typically includes the date of resignation, a brief explanation for leaving, and an expression of gratitude towards the employer for the opportunity given. Example of a resignation letter you can send to the HR department. Pick a resume template.