The letter must explain who is gifting the money, where the donor's funds are coming from and the relationship between the donor and the recipient. The purpose of this letter is to document that the money does not need to be repaid as well as the donor's name, contract information, and relationship to you.The goal of a gift letter is to provide the lender with proof of where the funds came from. If you're looking to use a gift letter from your family to fund a down payment, make sure you have the legal documentation necessary. Any gifts given or to be given must be documented with a gift letter. A gift letter for a mortgage shows your lender that you don't need to repay gift money toward your down payment. In most cases, documentation in the form of a gift letter will be required. Keep in mind, the amount of the transfer must match what's stated in the gift letter. FHA loan gift funds. Your mortgage gift letter or others need to include all the basic information so that you don't have to face any problems in the future.