How to write a resignation letter that's effective immediately? Commence your letter with a formal salutation and a concise introductory paragraph.Just keep it short and sweet. Don't go into story telling mode. We've rounded up tips and examples for writing a resignation letter that'll help you maintain work relationships long after leaving a company. Explain only what is necessary. Give a clear reason for leaving, but there is no need to over-explain. I am writing to let you know that I will be leaving my current position at CrossPay on September 8, 2024. Thank you for your consideration. I wish you and the company the best in the future.