15 Year Mortgage Double Payment Calculator

This calculator helps you determine how making double payments on your 15-year mortgage affects your interest savings and payoff timeline. By paying twice as much each month, you can significantly reduce the total interest paid and shorten the loan term.

How the Double Payment Plan Works

When you make double payments on your mortgage, you're essentially paying the standard monthly amount plus an additional equal amount. This strategy can be particularly effective for 15-year mortgages because:

The shorter term means you'll pay off the loan faster than with a 30-year mortgage
You'll pay less interest over the life of the loan
The extra payments will reduce your principal balance more quickly

Important Considerations

While double payments can save you money and time, they also mean you'll be making larger payments each month. Make sure your budget can accommodate these higher payments before committing to this strategy.

How It Affects Your Loan

The double payment plan works by:

Calculating your standard monthly payment
Adding an equal amount to create the double payment
Applying the full amount to your principal balance
Reducing the remaining balance more quickly than with regular payments

This approach is particularly effective for 15-year mortgages because the shorter term means you'll pay off the loan faster than with a 30-year mortgage. The extra payments will reduce your principal balance more quickly, allowing you to pay off the loan in half the time.

Using the Calculator

Our calculator makes it easy to see how a double payment plan affects your 15-year mortgage. Simply enter your loan details and see the results instantly.

How to Use the Calculator

Enter your loan amount in the first field
Input your annual interest rate
Select the loan term (15 years)
Click "Calculate" to see your results

The calculator will show you:

Your standard monthly payment
Your double payment amount
Total interest saved
New payoff date
A chart showing your amortization schedule

Formula Used

The calculator uses the standard mortgage payment formula:

M = P [ i(1 + i)^n ] / [ (1 + i)^n - 1 ]

Where:

M = Monthly payment
P = Principal loan amount
i = Monthly interest rate (annual rate / 12)
n = Number of payments (loan term in years × 12)

The double payment is simply 2 × M.

Worked Example

Let's look at an example to see how the double payment plan works in practice.

Example Scenario

Assume you have a $150,000 15-year mortgage at 4.5% annual interest.

Payment Type	Monthly Payment	Total Interest	Payoff Date
Standard	$1,030.48	$18,162.40	April 2028
Double Payment	$2,060.96	$1,662.40	October 2026

In this example, making double payments:

Reduces your monthly payment from $1,030.48 to $2,060.96
Saves you $16,500 in interest over the life of the loan
Shortens your payoff date by 18 months

Key Takeaway

This example shows how making double payments can significantly reduce your interest costs and pay off your mortgage faster. However, the exact savings will depend on your specific loan terms and interest rate.

Frequently Asked Questions

Is it better to make double payments or extra payments?

Double payments are more effective than extra payments because they reduce your principal balance more quickly. However, they also mean you'll be making larger payments each month, so make sure your budget can accommodate them.

Can I make double payments on any type of mortgage?

Double payments can be made on any type of mortgage, including fixed-rate and adjustable-rate mortgages. However, check with your lender to ensure they allow double payments and understand the impact on your loan terms.

Will making double payments hurt my credit score?

Making double payments can actually help improve your credit score by reducing your credit utilization ratio and demonstrating responsible borrowing. However, check with your lender first to ensure they allow double payments and understand the impact on your loan terms.