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. Gift Letter For Mortgage Template.Your lender might give you a template to follow if you tell them you're using a gift for your down payment. 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. Spouses may not file a joint gift tax return. Each individual is responsible to file a Form 709. A gift letter must contain the donor's name, the gift's value, confirmation that the gift is not to be repaid, and the donor's signature. A gift letter is an important, formal, legal piece of documentation that can help explain that a (usually rather large) sum of money was gifted to you. A message from Town Supervisor Don Clavin.