Learn how to write a short notice resignation letter with this stepbystep guide, template and examples of formal resignation. Commence your letter with a formal salutation and a concise introductory paragraph.In the opening paragraph, clearly state that you are resigning from your position. Keep it short and to the point. There's no reason to draw this letter out beyond a single page. The heading with the date, company name, person's name, and position. I have decided to resign due to personal reasons that require my immediate attention. Also include a short reason for the resignation and your intended last day of employment at the company. Customer: I filed a letter of resignation with a 30 day notice in writing, as I believe was required for my position.