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. A gift letter for a mortgage shows your lender that you don't need to repay gift money toward your down payment.A short letter like this sample gift letter will cover all of the requirements your lender needs. A mortgage gift letter is a simple but essential document that assures lenders the funds you received are a gift, with no repayment expected. Here's a sample gift letter you can use to prove that the money is truly meant as an outright gift, with no expectation of repayment. A mortgage gift letter is a document that helps satisfy the requirement that a borrower's down payment funds come from legitimate sources. A gift letter is a note from a donor to your lender regarding cash funds for your mortgage down payment. Understand what a gift letter is, why you need it for a mortgage, and how to write one effectively to get your home purchase approved.