How to write a resignation letter that's effective immediately? Learn how to write an immediate resignation letter with our comprehensive guide, including tips, examples, and a customizable template.In this article, we cover everything you need to know about writing a resignation letter without notice and provide an example to get you started. Professional resignation letter examples for different reasons. Free templates and writing guide to resign on a positive note without feeling awkward. I am writing to announce my resignation, effective in 24 hours. The Florida Division of Emergency Management, in a lawsuit filed Dec. 30, said its effort to recover the overpayment has been unsuccessful.