You can ask, but they don't have to answer. They also don't have to be truthful, as admitting to discrimination of any kind is admission of an illegal action.Your letter should have a professional and informative tone, covering exactly why you're denying their rental application. Your polite rental application denial letter should clearly state the applicant's name as given on their original submission. Download a customizable rental application rejection letter template for landlords or property managers to professionally notify applicants.