Pay Off The Mortgage Balance. After you have the payoff letter, you can send the final payment to your mortgage lender.Depending on your lender, you may have to sign in to an online account, call a helpline, or send a formal letter to start the request process. Calculate how quickly you can pay off your mortgage if you increase your monthly payment. A 10day payoff refers to the time it takes for your new lender to pay off your old loans during a refinance. 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. There's probably an online form. A payoff request can be created and mailed for free. How long does it take to obtain a payoff?