Prior to putting a lump amount towards your home loan, understand your options - who took over abn amro mortgages. Mortgage recasting is when a lender re-amortizes the loan after the house owner makes a large lump sum payment. In order for your payment to change, the loan should be reamortized to reflect the lower primary balance. Assume you purchase a home and get a 30-year $500,000 loan at 3% interest.In five years, you have additional money and choose to put $100,000 towards your mortgage. Without modifying your home loan, your payment remains the like the amortization schedule is still based on the initial $500,000 mortgage, however the lump sum payment allows you to pay off the loan much quicker: in about 22 years instead of 30 - how many mortgages in one fannie mae.