Learn how to write an immediate resignation letter with our comprehensive guide, including tips, examples, and a customizable template. How to write a resignation letter that's effective immediately?Please accept this letter as a notice of my resignation. Start with a two weeks notice letter. This will serve as a formal, written documentation of your intent to leave and your transition timeline. Your resignation letter should be brief and to the point. You don't need to include lengthy explanations about why you are resigning. (For example, "I regret to inform you that I will be resigning from my position, effective immediately. Please accept this letter as my formal resignation. Today will be my last day of work.