What One Extra Mortgage Payment a Year Does

Quick answer: One extra mortgage payment a year, applied to principal, typically cuts about 4 to 6 years off a 30-year loan and saves tens of thousands of dollars in interest. On a $300,000 loan at 6.5%, the estimate is roughly $85,000 saved. The key is making sure the extra money is labeled “principal only.”

A 30-year mortgage is built to feel slow. Most of your early payments go to interest, so the balance barely moves for years. One extra mortgage payment a year is one of the simplest ways to change that, and the math is easier to see than most people expect.

Want to lower your rate while you attack the balance? You can request free options to lower your interest rate using the form on this page.

What one extra mortgage payment a year saves: the math

Here’s a standard example. These figures are estimates and ignore taxes, insurance and escrow, which don’t change with extra principal.

Scenario A: $300,000 loan, 6.5% fixed, 30 years

• Monthly principal and interest: about $1,896
• Total interest with no extra payments: about $382,600
• With one extra payment a year (about $158 extra per month): payoff in roughly 24 years, with about $295,000 in total interest
• Estimated savings: about 5 to 6 years and roughly $85,000 in interest

Scenario B: $300,000 loan, 4% fixed, 30 years

• Monthly principal and interest: about $1,432
• Total interest with no extra payments: about $215,600
• With one extra payment a year (about $119 extra per month): payoff in roughly 26 years, with about $182,000 in total interest
• Estimated savings: about 4 years and roughly $33,000 in interest

Same loan size, same habit, very different payoff. The higher your rate, the more each extra dollar is worth. To run your own numbers, try the extra principal payment calculator.

Why one payment a year does so much

It comes down to how interest is charged. Each month, your lender multiplies your remaining balance by your monthly rate. A smaller balance means less interest next month, and the savings snowball from there.

• Early dollars are the most powerful. An extra $1,896 in year one avoids a lot more interest over the loan’s life than the same $1,896 in year 20. As a rough estimate at 6.5%, that early payment avoids on the order of $10,000 in interest.
• You skip the interest on the interest. Every dollar of principal you remove stops generating interest for the rest of the loan.
• Your regular payment stays the same. The balance shrinks faster, so more of each later payment goes to principal. That’s how the loan ends years early.

Every extra dollar of principal stops earning interest for your lender for the rest of the loan.

Three ways to make the extra payment

You don’t need a lump sum sitting in the bank. Pick the method that fits your cash flow.

1. Add 1/12 each month. Divide your monthly principal and interest by 12 and add that to every payment. On a $1,896 payment, that’s about $158. This is the easiest method to automate.
2. Make one lump sum a year. Use a tax refund, bonus or side income. Earlier in the year is slightly better than later, since the balance drops sooner.
3. Go biweekly. Paying half your payment every two weeks produces 26 half-payments, which equals 13 full payments a year. Some servicers hold the halves until they can post them, so see our breakdown of whether biweekly mortgage payments really save money before you sign up for a program that charges a fee.

How to make sure the extra goes to principal

This is where people lose the benefit. If the servicer isn’t told what to do with the extra money, it may treat it as an early payment on the next installment. That doesn’t reduce your balance the way you want.

1. Pay your regular payment first. Make sure the full scheduled payment is posted for the month.
2. Use the “additional principal” option. Most servicer websites and apps have a separate field for it. Use it instead of just increasing your payment amount.
3. Write instructions on paper checks. Put your loan number and “apply to principal only” in the memo, and send it separately from your regular payment if mailing.
4. Don’t send it toward escrow. Extra principal reduces your loan balance, not your tax and insurance account.
5. Verify on your next statement. Look for the principal balance drop by exactly the extra amount. If it didn’t, call the servicer and ask them to reapply it.

It’s also worth checking your loan documents for a prepayment penalty. Most modern home loans don’t have one, but confirm before you start. Our guide to paying off your mortgage early compares seven strategies side by side.

If your next statement doesn’t show the balance drop by the extra amount, call and have it reapplied.

Before you start: when extra payments aren’t the best move

A mortgage is often your cheapest debt. Extra mortgage payments are a strong move only after the more urgent things are handled.

• High-interest debt comes first. A credit card at 22% costs far more than a mortgage at 6.5%. Put extra cash there first. Use the Debt Burn-Down Calculator to see the order, or review our debt payoff plans guide.
• Keep an emergency fund. Home equity is hard to get back out in a hurry. Cash is not.
• Consider the alternatives. Some people prefer investing the difference, especially with a low rate. We walk through that tradeoff in pay off your mortgage early or invest the difference.
• Look at your rate. If your rate is well above today’s market, refinancing may beat extra payments, or work together with them. The mortgage recast vs. refinance comparison explains your options.

Need money for the extra payment? A tax refund is a natural source, and our upcoming piece on using a tax refund to pay off debt covers how to split it. For the full picture, see the mortgage payoff guide.

A simple plan to start this month

1. Find your monthly principal and interest on your latest statement.
2. Divide it by 12. That’s your monthly extra amount.
3. Set up an automatic extra principal payment in your servicer’s portal.
4. Check the next statement to confirm the balance dropped.
5. Revisit once a year. Raise the amount when your income rises.

If your rate is high enough that extra payments feel like swimming upstream, request free, no-obligation options to lower your rate through the form on this page, or read about ways to lower your rate first.

FAQ

Is one extra mortgage payment a year worth it?

For most people with a 30-year loan, yes. It can take roughly 4 to 6 years off the term and save tens of thousands in interest, depending on your rate and balance. It’s worth less if you have higher-interest debt or no emergency savings.

Is it better to make one lump sum or add a little each month?

Both work. Adding 1/12 monthly is easier to automate, while a lump sum fits bonuses and refunds. The earlier the money hits principal, the more interest you avoid.

Will my payment go down if I pay extra?

No. Extra principal shortens your loan, but your required payment stays the same. If you want a lower payment after a big lump sum, ask your servicer whether it offers a recast.

Can my lender charge a penalty for extra payments?

Most modern mortgages don’t have prepayment penalties, but some do. Check your loan documents or ask your servicer before starting. A qualified housing counselor or loan professional can also help you read the fine print.

This article is educational, not financial advice. Figures are estimates, so confirm details with your servicer and consider talking with a qualified professional.

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