Which document serves as a personal promise to repay the loan?

The document that serves as a personal promise to repay the loan is the note. This is a critical instrument in the lending process, as it outlines the borrower's promise to repay the lender under specific terms, including the amount borrowed, interest rate, repayment schedule, and maturity date.

The note is a legally binding contract, indicating the borrower’s commitment to meet these obligations, and it can be used in court if the borrower defaults on the loan. This distinction is important, as while the mortgage and deed of trust provide security interests in the property, they do not contain the borrower's personal promise to repay the debt. The loan agreement typically encompasses broader terms and conditions of the loan but is not solely a promise to repay. Thus, the note is the fundamental document establishing the borrower's obligation to repay the loan.