15-Year vs 30-Year Mortgage: Which Saves More?

The choice between a 15-year and 30-year mortgage can change your total cost by six figures. Here is a clear, side-by-side breakdown so you can pick the right loan term for your budget and goals.

12 min read

Table of Contents

  • 1.The Short Answer
  • 2.Side-by-Side Comparison
  • 3.How Much Interest You Save
  • 4.The Case for a 15-Year Mortgage
  • 5.The Case for a 30-Year Mortgage
  • 6.A Middle Path: 30-Year With Extra Payments
  • 7.How to Decide

The Short Answer

A 15-year mortgage saves the most money. You get a lower interest rate, pay off your home in half the time, and can save well over $100,000 in interest on a typical loan. The catch is a much higher monthly payment.

A 30-year mortgage costs more in total interest, but the lower monthly payment gives you breathing room for savings, investing, and life's surprises. For many households, that flexibility is worth the extra cost.

There is no single "right" answer. The best term is the one you can sustain comfortably without starving your emergency fund or retirement accounts.

Side-by-Side Comparison

Here is how a $300,000 loan compares. We use 6.5% for the 30-year and 5.9% for the 15-year, reflecting the typical rate gap between the two terms.

Feature30-Year15-Year
Interest rate6.5%5.9%
Monthly payment (P&I)$1,896$2,509
Total interest paid$382,633$151,662
Total cost of loan$682,633$451,662
Interest saved~$230,000
Paid off in30 years15 years

The 15-year payment is about $613 higher per month, but it saves roughly $230,000 in interest and cuts 15 years off your loan. Your exact numbers depend on today's rates and your loan size, so run them through our mortgage payment calculator.

How Much Interest You Save

Two things make the 15-year loan so much cheaper: the lower rate and the shorter time that interest accrues. On a 30-year loan, you carry a large balance for decades, and interest piles up on that balance every single month.

Where Your Money Goes in Year 1

30-year: interest portion~85% of each payment
15-year: interest portion~58% of each payment

With a 15-year loan, far more of every payment goes straight to principal from day one, which is why you build equity so much faster.

The Case for a 15-Year Mortgage

Save well over $100,000 in interest on a typical loan
Lower interest rate than a 30-year loan
Build equity quickly and own your home outright in 15 years
Forces disciplined, faster debt payoff
Great if you want to be mortgage-free before retirement

Choose a 15-year loan if your income is stable, you already have a solid emergency fund, and you are on track with retirement savings. The higher payment should still leave room to invest.

The Case for a 30-Year Mortgage

Lower monthly payment frees up cash flow
More room to invest, save, or handle emergencies
Easier to qualify for a larger or better home
You can still pay extra to finish early when you can afford it
Safer if your income varies month to month

The risk of the 30-year loan is discipline. The lower payment only pays off if you actually invest or save the difference. If the extra cash disappears into lifestyle spending, you get the higher interest cost without the benefit.

A Middle Path: 30-Year With Extra Payments

Many buyers take a 30-year mortgage for the lower required payment, then add extra principal each month to pay it off faster. This keeps the low payment as a safety net while still shrinking your interest cost.

The trade-off: 30-year rates are usually higher than 15-year rates, so even with extra payments you will pay a bit more interest than a true 15-year loan. But you gain flexibility, which is valuable if your income is unpredictable.

How to Decide

Check the payment fits

Your total housing cost should stay near or below 28% of gross income, even on the 15-year payment.

Protect your safety net

Do not choose the 15-year if it drains your emergency fund. Three to six months of expenses come first.

Do not skip retirement

If the higher payment stops you from getting a full 401(k) match, the 30-year is usually smarter.

Run the real numbers

Use current rates and your actual loan amount to compare both options before you commit.

Compare Both Loan Terms With Real Numbers

Plug in your home price and current rates to see the exact monthly payment and total interest for a 15-year and 30-year mortgage.

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This guide is for educational purposes only and does not provide financial advice. Rates and figures are illustrative examples.