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.This resignation letter sample provides your employer with a letter for your file and also suggests that you've done everything you can to remain professional. 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. I am writing to announce my resignation, effective in 24 hours. This job aid describes the process for submitting your resignation letter.