A meaningful retirement letter needs to be professional, polite, and friendly in tone. Below we provide resources on how to write a retirement letter correctly using our downloadable sample, helpful guide, and template.State your desired retirement date (your last day) and your thoughts on a transition plan in the body of the letter. Use singlespacing throughout your resignation letter. Align all paragraphs to the left. Use one of our resignation letter templates. The complete guide to writing your resignation letter including expert tips, free copyable samples, and templates. Give your employer at least two weeks' notice. Employees with a long tenure at the company typically give a month's notice or more. In the body of the letter, state your intended retirement date (your last day) and your thoughts on a transition plan.