Create automatic loan amortization schedule table with PMT, IPMT, PPMT formulas in Microsoft Excel The tutorial shows how to build an amortization schedule in Excel to detail periodic payments on an amortizing loan or mortgage.If you add an extra payment the calculator will show how many payments you saved off the original loan term and how many years that saved. 13, Payment number, Payment date, Beginning balance, Scheduled payment, Extra payment, Total Click the "File" menu and click the "New" option. Loan Amortization Schedule, This spreadsheet creates an amortization schedule for a fixed-rate loan, with optional extra payments.