Learn how to write a professional resignation letter with our step-by-step guide, easy to use templates and helpful tips. We've rounded up tips and examples for writing a resignation letter that'll help you maintain work relationships long after leaving a company.I am writing to inform you that I will be resigning from my position as (Title) at (Company Name). Below is a sample union resignation letter. You should check your union's constitution and bylaws to see if it is specific to whom a resignation must be sent. I am writing to notify you of my resignation from my position as (job title) at (company name). My resignation is effective immediately. The purpose of the letter is to inform the board of the decision to step down and to provide details such as the effective date of the resignation.