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.I am providing (borrower's name), my (relationship), with a gift of (amount of the gift) toward the purchase of their home. Use these stepbystep instructions for accepting a cash downpayment gift on a home, including a readytouse mortgage gift letter template. A mortgage gift letter is a simple but essential document that assures lenders the funds you received are a gift, with no repayment expected. A gift letter is a note from a donor to your lender regarding cash funds for your mortgage down payment. • Gift Letter Form.