Mortgage note is a written promise to repay a specified sum of money plus interest at a specified rate. While the mortgage itself pledges the title to real property as security for a loan, the mortgage note states the amount of debt and the rate of interest, and makes the borrower who sign's the note personally responsible for repayment. What is the advantage of a Mortgage note over a Tax lien or Tax deed Certificate? A Mortgage note will allow you to collect the interest on a monthly basis. Tax lien and Tax deed certificates are only paid when the Lien or Deed is redeemed.