How to write a resignation letter that's effective immediately? In this article, we share tips for writing a short, simple resignation letter and offer examples for you to reference when creating your own.A resignation letter should provide a clear time frame of when you plan to terminate your position. Specifically state the day your resignation is official. Here is a form that you can print out and keep on hand to have your employees complete anytime one of them resigns. (For example, "I regret to inform you that I will be resigning from my position, effective immediately. Click on the image to download our immediate resignation letter example.