The following are the things to keep in mind when writing an immediate resignation letter: Write the date first. Explain only necessities.Start with the facts and be direct. Learn how to write a short notice resignation letter with this stepbystep guide, template and examples of formal resignation. Due to health concerns, I must resign immediately. State your position on the day of resignation: Always mention the position you held in the office on your last working day. If your letter of resignation had a timeline, there's nothing to do. Please accept this letter as my formal resignation. Today will be my last day of work. Employers may also want to consider the impact an immediate separation would have on remaining employees.