15-year vs. 30-year mortgage: which should you choose?

When you take out a mortgage, the term — how many years you have to repay — is one of the biggest decisions you will make, and it usually comes down to two choices: 15 years or 30 years. They are not just "faster" versus "slower." They represent a genuine trade-off between total cost and monthly flexibility, and the right answer depends on your situation, not a rule.

The core trade-off

A 15-year mortgage has a higher monthly payment but a lower interest rate and dramatically less total interest. A 30-year mortgage has a much lower payment but costs far more over its life and usually carries a slightly higher rate. Here is the same $300,000 loan both ways, using representative rates:

The 15-year payment is about $613 more a month — but it saves roughly $231,000 in interest and you own the home free and clear in half the time. That is the whole decision in one table.

Why the 15-year saves so much

Two forces stack up. First, lenders charge a lower rate on 15-year loans because they get their money back sooner and take on less risk. Second, and bigger, you are simply paying interest for 15 years instead of 30. As our amortization guide explains, a mortgage front-loads interest — so cutting the years off the back end removes a lot of interest-heavy time.

When the 30-year is the smarter choice

Lower lifetime cost is not automatically the right goal. The 30-year wins when:

• The lower payment protects your budget. A smaller required payment leaves room for an emergency fund, retirement contributions, and life's surprises. A house that makes you "payment-poor" is a risk, not a win.
• You would invest the difference. If you would reliably put that ~$613/month into a retirement account earning more than your mortgage rate, the math can favor the 30-year plus investing. The key word is reliably — see our pay-off-debt-or-invest guide.
• You value flexibility. The 30-year lets you pay as if it were a 15-year in good months and drop back to the lower payment in tight ones — a freedom the 15-year does not give you.

How to decide

• Choose 15-year if you can comfortably afford the higher payment and still fund retirement and an emergency fund. The guaranteed interest savings are enormous.
• Choose 30-year if the higher payment would squeeze out saving and investing, if your income is variable, or if you genuinely will invest the difference.

Whatever you choose, run your real numbers first. Enter both terms and rates in the loan calculator and compare the "total interest" figures — the gap is exactly what the decision is worth.

Educational information only, not financial advice. Rates are illustrative and exclude taxes, insurance, and fees.