My mortgage is 340,000 yuan, *** 14, and the monthly payment is 3 100. I started making monthly payments last March. Suppose I pay off the remaining loan in one lump sum, how much do I need to pay back? The monthly repayment is 3 100, so you are a commercial loan, with benchmark interest rate and equal principal and interest repayment. The principal is about 1248 yuan per month. Repayment 15 months, * * * 46,500 yuan, including principal 18720 and interest of 27,780. The loan is 340,000 yuan, and the remaining principal is 32 1280 yuan. If one-time repayment is made, the principal will be returned to 32 1280. I wonder if your bank has a penalty interest. Look, it's in the contract. The repayment interest of 27780 plus the penalty interest is your repayment interest.