Third Party Payoff Request Form. All third-party payoff requests require prior authorization.Click this link to go to the New User Registration page and complete the New User Registration. A mortgage payoff letter can come in two forms. One form tells borrowers the remaining principal amount and interest they have to pay to close out the loan. This handy guide breaks down the home loan process to make borrowing for residential real estate smooth and simple. Phone: (877) 772-9633. Use this phone number when requesting loan payoffs from Direct Mortgage, Corp. City of South Salt Lake. Use SmartAsset's free Utah mortgage loan calculator to determine your monthly payments, including PMI, homeowners insurance, taxes, interest and more.