To add a monthly escrow amount to the loan amortization schedule in Excel, you can follow these steps: Insert a new row below the last payment row. Mortgage amortization is the process of paying down your mortgage over the course of your term.An amortization schedule shows how those payments are applied. To use our amortization calculator, type in a dollar figure under "Loan amount. Microsoft Excel Mortgage Caculator XLS Worksheet. Use our free commercial real estate loan calculator to calculate the details of a commercial mortgage easily and quickly. Check out the web's best free mortgage calculator to save money on your home loan today. The rounding option is for comparison with other calculators that do not round the payment or interest.