Resignation acceptance letter template. Resignation Acceptance Email templates: Discover how to write an effective resignation acceptance letter.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. Below you'll find a sample resignation letter informing the employer that the employee is resigning due to a new job opportunity. Use an attractive header with your personal contact info, include the recipient's name, company and address, and include the date. In this guide, I'll cover how to effectively resign from a board, the key elements to include in your letter, and provide examples of resignation letters.