Below we provide resources on how to write a retirement letter correctly using our downloadable sample, helpful guide, and template. 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.State your desired retirement date (your last day) and your thoughts on a transition plan in the body of the letter. Use one of our resignation letter templates. The complete guide to writing your resignation letter including expert tips, free copyable samples, and templates. Your retirement resignation letter should begin with a header that states the contact information of the sender and addressee as well as the date. Your retirement resignation letter should begin with a header that states the contact information of the sender and addressee as well as the date.