One Extra Mortgage Payment Per Year: How Much Does It Save?

One of the most effective and overlooked strategies for reducing mortgage costs is simply making one extra principal payment per year. It does not require refinancing, does not involve any fees, and does not demand significant financial sacrifice. Yet on a standard 30-year mortgage, a single additional annual payment shaves roughly four to five years off the loan term and saves tens of thousands of dollars in interest.

The math is straightforward, the mechanics are simple, and the results compound over time in a way that surprises most homeowners when they actually run the numbers.

How One Extra Payment Per Year Works

When you make your standard monthly mortgage payment, it is divided between interest and principal according to your amortization schedule. In the early years of a 30-year mortgage, the split is heavily weighted toward interest. On a $300,000 loan at 6.5%, for example, the first monthly payment of roughly $1,896 allocates about $1,625 to interest and only $271 to principal.

When you make an extra payment — directed entirely to principal — you skip ahead in the amortization schedule. That $1,896 applied to principal eliminates a future month of payments where most of the money would have gone to interest. Each dollar of early principal repayment has an outsized effect relative to the same dollar paid later.

Making one extra payment per year effectively adds 8.3% more principal reduction annually than your standard schedule provides. Over a 30-year loan, that consistent extra payment reduces the term to approximately 25 to 26 years and eliminates the interest that would have accumulated in those final years.

The Numbers on a Typical Loan

On a $350,000 mortgage at 6.5% interest with a 30-year term:

• Standard monthly payment: $2,213 (principal and interest)
• Total interest over 30 years at standard schedule: approximately $446,600
• With one extra monthly payment per year: payoff in approximately 25.5 years
• Interest savings: approximately $64,000

The extra payment amount — $2,213 once annually — saves $64,000. The return on that investment is substantial.

The exact figures vary based on your loan balance, interest rate, and when in the loan term you begin making extra payments. The earlier you start, the more dramatic the effect, because you are eliminating high-interest months early in the amortization schedule.

The Biweekly Mortgage Strategy

A biweekly payment schedule is the most common method for implementing this strategy without the discipline challenge of a single annual lump sum.

Instead of making one monthly payment, you make half a payment every two weeks. Here is why this produces an extra payment per year: there are 52 weeks in a year, which means 26 biweekly payments — equivalent to 13 monthly payments rather than 12. That thirteenth payment goes entirely to principal.

The biweekly approach has a practical advantage over a single annual extra payment: the amounts are smaller and spread throughout the year, which is easier to manage on most budgets. Half your monthly payment every two weeks is less noticeable than a full extra payment in December.

The mechanics can be set up in a few ways:

Through your servicer: Some mortgage servicers offer formal biweekly programs. Be cautious — some charge setup or monthly fees, which erode the savings. If the program costs money, calculate whether the fee is justified by your interest savings over your expected time horizon in the home.

Through your bank: Set up an automatic transfer of half your monthly payment every two weeks into a separate account, then make one full payment plus one extra principal payment per year. This accomplishes the same result without paying a servicer fee.

Manually: Make your standard 12 monthly payments plus one additional principal payment per year, timed to your cash flow — an annual bonus, tax refund, or any month when you have more flexibility.

How to Calculate Your Specific Payoff

The impact of extra payments is specific to your loan amount, interest rate, and current payoff timeline. A mortgage calculator with extra payment functionality — many are available free online — can show you the exact payoff date and interest savings based on your inputs.

The inputs you need are:

• Current loan balance
• Interest rate
• Remaining loan term
• Extra payment amount and frequency (monthly, annual, one-time)

When you run this analysis, look at both the payoff date and the cumulative interest savings. Some people are surprised to find that modest extra payments — even $100 or $200 per month — produce meaningful results over a long horizon.

Extra Payments vs. Other Financial Priorities

Making extra mortgage payments is not automatically the right financial move. The correct comparison is between your mortgage interest rate and what you could earn elsewhere.

If your mortgage rate is 6.5% and your emergency reserve is underfunded, build the reserve first. A three-to-six month cash cushion protects against the scenario where a financial shock forces you to miss mortgage payments — which would be far more costly than the interest you saved with extra payments.

If your mortgage rate is 6.5% and you carry credit card balances at 22%, eliminating that debt produces a guaranteed 22% return — substantially higher than the 6.5% you save on mortgage interest.

If your mortgage rate is 6.5% and your employer offers a 401(k) match that you are not capturing, take the match first. A 50% or 100% employer match is a guaranteed return that dwarfs the mortgage interest savings.

After those priorities are met, extra mortgage payments become competitive. A 6.5% guaranteed return on prepayment is not available in most fixed-income investments, and the psychological value of owning your home outright sooner has real worth for many people.

What to Say to Your Servicer

When making extra payments, you must specify that the additional funds should be applied to principal. If you simply send extra money without instructions, many servicers will apply it to your next scheduled payment rather than to principal, which advances your payment date without reducing your balance.

The clearest approach: write "apply to principal only" on any check, or select the principal-only option in your online account when submitting the payment. If your servicer has a formal process for designating payments, use it. Verify on your next statement that the extra amount reduced your principal balance as expected.

Tracking Your Progress

One of the most motivating aspects of extra payment strategies is how quickly you can see progress when you track it systematically. Your monthly mortgage statement shows your remaining balance, but most statements do not show the cumulative effect of extra payments on your projected payoff date.

Running an updated payoff calculation every six months or annually — using your current balance, your interest rate, and your extra payment history — gives you a concrete picture of how many months you have shaved off the loan. Watching a 30-year payoff date move to 28, then 26, then 24 years is tangible evidence that the strategy is working.

This kind of tracking also helps you decide whether to adjust your extra payment amount over time. If your income increases or a debt is paid off, redirecting that freed-up cash to extra mortgage payments accelerates the timeline further. Conversely, if financial circumstances change and you need to pause extra payments, you still keep all the progress you made — your balance is simply lower than it would have been, and your required payments remain the same as always.

If you are evaluating your loan and planning your payoff strategy, the Mortgage Worksheet includes a payoff calculator section that lets you model different extra payment scenarios — monthly, annual, or lump sum — alongside your existing loan details, so you can set a realistic target and track progress toward it.