The tutorial shows how to build an amortization schedule in Excel to detail periodic payments on an amortizing loan or mortgage. 13, Payment number, Payment date, Beginning balance, Scheduled payment, Extra payment, TotalThis Excel spreadsheet makes it easy to view the amortization of a home loan with optional extra monthly payments. Excel Amortization Schedule With Irregular Payments v. 2 - Free download as Excel Spreadsheet (. Adding extra principal payments in order to pay off the loan earlier than the loan contract calls for. In this tutorial we will add this feature. Want to know the impact of "extra payments" on your mortgage? Check out this easy to use Excel mortgage calculator. This calculator will help you figure out your regular loan payments and it will also create a detailed schedule of payments.