This article will address how to write a retirement letter of resignation and provide an example that you can use as a template for your own retirement letter. Your retirement resignation letter should begin with a header that states the contact information of the sender and addressee as well as the date.To resign from your position, complete and submit a resignation letter to your supervisor at least two weeks, or as soon as possible, before your last day. Professional resignation letter examples for different reasons. Free templates and writing guide to resign on a positive note without feeling awkward. In the opening paragraph, make it clear that you are retiring.