An annual bonus letter is a formal document from an employer to an employee, informing them of their annual bonus award. It typically includes the bonus amount, the reason for the bonus (such as performance achievements or company profitability), and the payment date. The letter often expresses appreciation for the employee's contributions and highlights their role in the company’s success. Its tone is positive and congratulatory, aiming to recognize the employee’s hard work and motivate continued performance. It also serves as official documentation of the bonus award.