Why should I write a resignation letter? Resignation letters are professional courtesies that extend your professionalism, even in the last.Taylor discusses 6 key aspects of writing a resignation letter, including when to give notice, what to say, how to format it, and how to deliver it. Use one of our resignation letter templates. The header at the top of the resignation letter (the same thing as a letterhead) should include your name, address, phone number and email. Start with a two weeks notice letter. This will serve as a formal, written documentation of your intent to leave and your transition timeline. This sample resignation letter is available for use on UpCounsel. A good resignation letter is brief, succinct, and expresses gratitude to your employer. Use this sample to part ways amicably.