Money Saving Expert Mortgage Calculator Overpayment

This mortgage overpayment calculator helps you determine how much you can save by making extra payments on your mortgage. By understanding the impact of overpayments, you can reduce your interest costs and pay off your mortgage faster.

How the Mortgage Overpayment Calculator Works

The calculator estimates your potential savings by considering your current mortgage balance, interest rate, and the amount you plan to overpay. It uses standard mortgage amortization formulas to project how your loan balance will change over time with additional payments.

Key Concepts

Mortgage amortization: The process of paying off a mortgage loan in regular installments
Interest-only payments: Payments that cover only the interest portion of the loan
Principal repayment: Payments that reduce the outstanding loan balance

By making regular overpayments, you can significantly reduce the total interest paid over the life of your mortgage. The calculator shows you how much you'll save in interest costs and how much faster you'll pay off your loan.

How to Use This Calculator

Enter your current mortgage balance in the "Current Balance" field
Input your current interest rate in the "Interest Rate" field
Specify the amount you plan to overpay each month in the "Monthly Overpayment" field
Click the "Calculate" button to see your potential savings
Review the results to understand how your overpayments will impact your mortgage

The Formula Used

The calculator uses the following formula to estimate your savings:

Total Savings = (Total Interest Without Overpayment) - (Total Interest With Overpayment)

Where:

Total Interest Without Overpayment = Current Balance × (Interest Rate / 12) × Loan Term (in months)
Total Interest With Overpayment = (Current Balance - Total Overpayments) × (Interest Rate / 12) × (Loan Term - (Overpayment Period / 12))

Worked Example

Let's look at an example to understand how the calculator works. Suppose you have a £200,000 mortgage with a 3.5% interest rate. You plan to make an extra £100 each month for 5 years.

Metric	Without Overpayment	With Overpayment
Total Interest Paid	£126,667	£101,667
Total Savings	-	£25,000
Loan Term Reduction	-	5 years

In this example, making £100 extra payments each month for 5 years would save you £25,000 in interest and reduce your loan term by 5 years.

Frequently Asked Questions

How does overpaying my mortgage work?

Overpaying your mortgage means making additional payments beyond your regular monthly installment. These extra payments go directly toward reducing your principal balance, which lowers the total interest you'll pay over the life of your loan.

Is it better to overpay at the beginning or end of my mortgage?

Overpaying at the beginning of your mortgage term is generally more beneficial because you'll save more in interest costs. The longer you leave your mortgage, the more interest you'll pay, so reducing the balance early can have a significant impact on your total savings.

Can I overpay my mortgage if I have an offset account?

Yes, you can overpay your mortgage even if you have an offset account. An offset account allows you to use your savings to reduce your mortgage balance, but you can still make additional payments beyond what's covered by your offset.

What happens if I stop making overpayments?

If you stop making overpayments, your mortgage will continue according to its original terms. The interest will continue to accrue, and your loan term will extend. The savings you would have made from overpaying will be lost.