What's the interest rate difference between a 15-year and 30-year mortgage?

15-year mortgages typically carry rates 0.5% to 1.0% lower than 30-year mortgages. As of 2026, a 15-year fixed averages around 5.8%–6.0% compared to 6.5%–7.0% for a 30-year. This rate discount is a big part of why 15-year loans save so much in total interest.

Which mortgage saves more money — 15-year or 30-year?

A 15-year mortgage always saves more in total interest. On a $300,000 loan at 6.7% vs 5.9%, the 15-year saves roughly $245,000 in interest over the life of the loan. But the monthly payment is about 60% higher, which is why most buyers still choose 30-year terms.

Can I switch from a 30-year mortgage to a 15-year later?

Yes — you can refinance a 30-year mortgage into a 15-year loan at any time. You'll need to qualify for the new loan and pay closing costs (typically 2%–5% of the loan amount). Many homeowners refinance into 15-year terms 5–10 years into their mortgage when income is higher.

Can I get the benefits of a 15-year mortgage by prepaying a 30-year?

Partly. Making extra payments on a 30-year mortgage can pay it off in 15 years, but you'll still pay the higher 30-year interest rate. On a $300K loan, paying off a 30-year at 6.7% in 15 years costs about $32,000 more in interest than using a true 15-year at 5.9%. The flexibility of a 30-year with optional prepayments is still valuable.

15-Year vs 30-Year Mortgage: The Real Numbers

On a $300,000 mortgage at 6.7%, a 30-year fixed costs $1,936/month while a 15-year at 5.9% costs $2,515/month. That's $579 more per month — but the 15-year saves $244,656 in total interest and builds equity nearly three times faster. Here's the full breakdown.

Side-by-Side: 15-Year vs 30-Year Mortgage

All numbers based on a $300,000 loan with 20% down, excluding taxes and insurance:

Metric 30-Year (6.7%) 15-Year (5.9%)

Monthly Payment $1,936 $2,515

Total Interest $396,960 $152,304

Total Cost $696,960 $452,304

Equity at 5 Years $26,000 $72,000

Equity at 10 Years $62,000 $182,000

Year Mortgage-Free 2056 2041

The equity difference is staggering. After just 5 years, a 15-year borrower has $72,000 in equity — nearly triple the 30-year's $26,000. That's the result of both the lower rate and the accelerated amortization schedule.

When a 15-Year Mortgage Wins

You can comfortably afford the higher payment. If the $579/month difference doesn't strain your budget, the 15-year is mathematically superior.
You want to be mortgage-free before retirement. A 15-year loan taken at age 45 puts you mortgage-free by 60.
You're buying well below your max. If you qualify for a $500K loan but buy at $300K, the 15-year payment is still manageable.
You hate paying interest. The 30-year borrower pays $396,960 in interest — more than the house itself.

When a 30-Year Makes More Sense

Cash flow flexibility matters. A lower required payment leaves room for emergencies, investing, or lifestyle.
You'll invest the difference. If you invest the $579/month savings at 7%, you'd accumulate roughly $700,000+ over 30 years — potentially beating the interest savings.
You want the option to prepay. A 30-year gives you the flexibility to make extra payments when you have cash and skip them when you don't.
This is your first home. First-time buyers often stretch their budget — better to have lower mandatory payments while building career stability.

The Hybrid Strategy: 30-Year With Aggressive Prepayments

Many smart buyers take the 30-year for flexibility, then pay it like a 15-year. On a $300K 30-year at 6.7%, adding an extra $579/month (the 15-year payment difference) pays off the loan in about 16 years and saves roughly $212,000 in interest. You lose about $32,000 in extra savings compared to the true 15-year rate, but gain the flexibility to dial back payments anytime.

Run Your Own Numbers

The numbers above use $300,000 and today's rates. Your situation is different. Use our mortgage calculator to compare 15-year vs 30-year payments, total interest, and amortization schedules with your exact loan amount, rate, and down payment.

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