A rental application denial letter, also known as an adverse action letter, is a formal document that a landlord or property manager sends to applicants. We discuss everything you need to know about turning down applicants and provide a template for your convenience.If the application isn't fully completed, you don't need to give any further reason to reject. In this article, we'll talk you through what's included in a rental application denial letter and even give you a free template to use. Your letter should have a professional and informative tone, covering exactly why you're denying their rental application. You should always act fairly, professionally, and compliantly when rejecting rental applications. Check out our guide below for the best practices. You must be truthful on your rental application.