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 mortgage gift letter is a statement that assures your lender the money that came into your account is a gift and not a loan.A gift letter is a note from a donor to your lender regarding cash funds for your mortgage down payment. A gift letter is a piece of legal, written correspondence explicitly stating that money received isn't expected to be repaid. This guide explains how to document gift funds for a mortgage and meet lender requirements. A gift letter for a mortgage is proof to the lender that money you've been given for your home purchase is a gift, not a loan to be repaid. 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 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. As noted earlier, your bank should provide a gift letter template for you to complete. If you plan on getting gift funds from a friend or family member, you'll need a gift letter confirming your relationship to the giver.