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. The purpose of this letter is to document that the money does not need to be repaid as well as the donor's name, contract information, and relationship to you.You can use gifted funds to make a down payment, but your mortgage lender will want to know some details before they allow you to use it. If you go through a bank they will provide the gift letter form to you to get completed. If someone provides a handwritten letter it is filed away. The person who gave you the money must write and sign the gift letter as well as provide their personal information. To use gift funds, you must provide a gift letter proving the money is not a loan. Mortgage lenders generally provide a gift letter template for you to use and share with the donor(s). The red flags would be with the mortgage company or IRS. If it wasn't a loan, gift it back.