Mortgage Recast Calculator

The Mortgage Recast Calculator is a practical and straightforward tool that shows homeowners exactly how much they can save in monthly payments and total interest by making a lump sum payment toward their mortgage principal and having the loan recast. Unlike refinancing — which involves a full application process, credit checks, closing costs, and a new interest rate — mortgage recasting is a much simpler arrangement where you pay a large amount toward your principal and your lender recalculates your monthly payment based on the reduced balance, keeping your original interest rate and remaining loan term intact. The savings can be significant, and this calculator lets you see the full picture before you commit to anything.

Whether you have recently received a work bonus, an inheritance, proceeds from a property sale, or any other windfall that you are considering putting toward your home loan, this calculator tells you precisely what the financial impact would be — including how much your monthly payment drops, how much total interest you save over the remaining life of the loan, and a side-by-side comparison of your original and recast amortization schedules.

How to Use the Mortgage Recast Calculator Online

Setting up the calculation is simple and takes just a minute. Here is how to use it:

Step-by-Step Instructions:

• Enter your original loan amount — for example $300,000 — in the first field. This is the total amount you originally borrowed when you took out the mortgage.
• Enter your current principal balance — for example $250,000 — which is the remaining amount you still owe on the loan today, after all payments made so far.
• Enter your interest rate — for example 4.5% — and select your original loan term in years — for example 30 years — along with the time remaining on your loan — for example 25 years.
• Enter the lump sum payment you are planning to make toward the recast — for example $50,000. This is the amount that will be applied directly to your principal balance before the monthly payment is recalculated.
• Click “Calculate Recast” and your full results will appear instantly, showing your monthly payment savings in both dollar amount and percentage reduction, your before and after monthly payments, and your total interest savings across the remaining loan term. For example, a $50,000 lump sum on the above scenario reduces the monthly payment from $1,520.06 to $1,266.71, saving $253.35 every month and $76,005 in total interest.
• Switch between the Summary tab and the Amortization tab to view either a clean overview of the loan details and payment comparison, or a full month-by-month and year-by-year schedule showing the original versus recast payments, principal, interest, and remaining balance side by side.
• Export your results as a PDF using your browser’s Print function — Ctrl+P on Windows or Cmd+P on Mac — and selecting Save as PDF for a clean, single-page record suitable for personal financial planning or sharing with your lender.

Why Use the Mortgage Recast Calculator Online?

• Complete Before and After Comparison: The calculator shows your original and recast monthly payments, total interest figures, and overall savings all together in one summary, so you can immediately see the full financial impact of the recast without having to piece the numbers together from separate calculations.
• Detailed Amortization Schedules: The amortization tab provides a full payment-by-payment breakdown of your original loan versus the recast loan, showing principal paid, interest paid, and remaining balance for each period, which is far more informative than a simple savings figure and gives you a genuine understanding of how the recast reshapes your loan over time.
• Monthly and Yearly Schedule Views: The amortization schedule can be toggled between monthly and yearly views, making it easy to look at the detailed month-by-month picture when you need precision or zoom out to a year-by-year summary when you want a quicker read of the long-term trajectory.
• No Refinancing Complexity: Mortgage recasting is often a smarter option than refinancing for homeowners who are happy with their current interest rate and just want lower monthly payments. This calculator helps you evaluate the recast option clearly so you can have an informed conversation with your lender without needing a financial advisor to interpret the numbers for you.
• PDF Export Ready: The results page is optimized for clean, single-page PDF output through your browser’s print function, making it easy to save a documented record of your recast projections for budgeting purposes or to share directly with your mortgage lender during a recast request discussion.
• Ideal for Homeowners with Lump Sum Funds: Whether you are putting a bonus, an inheritance, investment proceeds, or savings toward your mortgage, this calculator gives you the exact numbers you need to decide whether recasting makes more financial sense than investing that money elsewhere or applying it in a different way.
• Free and Accessible: No registration, no fees, and works on any device, so you can run your mortgage recast calculation from your phone, tablet, or desktop whenever you are ready to explore your options.