In the US I would say it's not safe, at least not entirely. That's communication with your prior employer usually from the email address they provided.Explore more articles. How to write a resignation letter that's effective immediately? They don't have to accept a resignation. You're handing it in. 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. When you write a letter of resignation, you have quit. Offering to stay two weeks is the standard in an effort to help transition the work etc. This letter accepts an employee's resignation, noting their last day will be after serving out their required notice period according to their contract.