Your letter should have a professional and informative tone, covering exactly why you're denying their rental application. Download a customizable rental application rejection letter template for landlords or property managers to professionally notify applicants.Good evening, BP. I'm writing my Tenant Rejection Letter and found some reasons online as to why a tenant is denied their application. You should always act fairly, professionally, and compliantly when rejecting rental applications. Check out our guide below for the best practices. All individuals over the age of 18 MUST fill out a separate application if they will be living on the property. 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. This guide will help landlords navigate the rental application denial process and provide a free rental application denial letter template. This guide will help landlords navigate the rental application denial process and provide a free rental application denial letter template. 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.