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. 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.The gift tax is the responsibility of the eligible person receiving the motor vehicle. It states how much you're getting and from whom. The lender is requiring me to write a gift letter stating I'm gifting my SO the down payment, with no expectation of being repaid. 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 written explanation provided to your mortgage lender when someone else gives you money toward a home purchase. Please be sure to fill this out form completely and submit with the other information requested below. If they refuse to answer all of your questions, there's a good chance you're in the middle of a scam. Don't respond and file a complaint with us.