15-Year vs 30-Year Mortgage: Which Is Right for You?

The Core Tradeoff

Every dollar you save on monthly payments with a 30-year mortgage is a dollar you pay in interest over time. The 30-year loan makes homeownership accessible by keeping payments low — but that accessibility comes at a significant long-term cost.

The 15-year mortgage forces you to build equity faster and pay dramatically less in total interest — but the higher monthly payment means you need a higher income to qualify, and less monthly cash flow flexibility.

Neither option is universally better. The right choice depends on your income stability, other financial goals, and how long you plan to stay in the home.

Side-by-Side Numbers: $350,000 Loan at Today's Rates

Using a $350,000 loan amount (after down payment) as a realistic example. Typical rate spread between 15 and 30-year loans is about 0.5–0.75% — lenders charge less for the shorter term because they take on less long-term risk.

Principal paid is the equity you build by paying down the loan. It excludes your down payment and any change in the home's value. Figures cover principal and interest only (no taxes, insurance, or PMI).

The 15-year mortgage saves $287,554 in interest on a $350,000 loan. That's a real number that reflects a real tradeoff against $702/month in higher payments. After five years, the 15-year borrower has paid off about 24% of the loan; the 30-year borrower, about 6%.

Compare with Your Own Numbers

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The Case for a 30-Year Mortgage

Lower required income to qualify

Lenders use your monthly payment to determine how much you can borrow. A $2,299 payment qualifies at a lower income than a $3,001 payment. If you're stretching to buy in a competitive market, the 30-year often makes the purchase possible at all.

Monthly cash flow flexibility

The $702/month difference is significant. That's money you could put toward an emergency fund, retirement contributions, college savings, or investing. If your employer matches 401k contributions and you're not maxing that out, the guaranteed return from those match dollars may outweigh the interest savings from a 15-year mortgage.

Optionality

With a 30-year mortgage, you're not locked in. You can make extra principal payments whenever you choose and effectively create your own "15-year" payoff schedule — without being forced to make the higher payment in months when cash is tight. This optionality is valuable.

Inflation works in your favor

A fixed mortgage payment becomes cheaper in real terms over time as inflation rises. The $2,299 payment you make in year 30 is worth far less in purchasing power than the same payment in year 1. This effect is stronger with a longer loan term.

The Case for a 15-Year Mortgage

Dramatically lower total cost

$287,554 in interest savings on a $350,000 loan is not a small number. On the 30-year loan, the interest alone ($477,730) comes to about 1.36x the amount you borrowed — you effectively pay for your home more than twice. The 15-year buyer's interest is about 54% of the loan amount.

Forced savings and equity

Humans are not great at voluntary savings. A 30-year buyer who plans to "invest the difference" often doesn't. The 15-year mortgage forces wealth-building automatically — by year 10, the 15-year borrower has paid down about 3.9x as much principal as a 30-year borrower on the same loan ($196,000 vs $51,000).

Lower interest rate

The 15-year rate is typically 0.5–0.75% lower. On a large loan, this rate difference alone saves tens of thousands of dollars — in this example, about $21,700 compared with a 15-year loan at the 30-year rate — on top of the savings from the shorter payoff timeline.

Retire with a paid-off home

If you're 45 and take a 15-year mortgage, you're debt-free at 60 — before retirement. A 30-year mortgage at 45 means payments until you're 75. For many buyers approaching middle age, this calculation is decisive.

Who Should Choose Each Option

Choose a 30-year if:

• You're stretching to afford the home you want and need the lower payment to qualify
• You have high-interest debt to pay off first (credit cards, personal loans)
• Your income is variable or you value monthly cash flow flexibility
• You're early in your career with strong income growth ahead
• You have no emergency fund yet and need to build one
• You're not maximizing employer 401k matching — invest there first

Choose a 15-year if:

• You can comfortably afford the higher payment without stretching
• You're mid-career or older and want to retire mortgage-free
• You have stable income and a solid emergency fund
• You're already maxing retirement contributions
• You know you'll stay in the home long-term (moving early erases the interest savings)
• Minimizing total lifetime housing cost is a priority

The "Invest the Difference" Argument

30-year advocates often say: take the lower payment, invest the $702/month difference, and you'll come out ahead. This argument has merit — but only if you actually invest the difference consistently for 30 years, and only if your investment returns exceed your mortgage rate.

At a 7% investment return and a 6.875% mortgage rate, the mathematical advantage of investing is small and the outcome is highly uncertain. At a 6.25% mortgage rate and a 7% return, investing wins — but by much less than most people assume after factoring in taxes on investment gains.

The honest answer: most people don't invest the difference. They spend it. If you have the discipline, a 30-year with consistent investing can work. If you don't, a 15-year forces the savings automatically.

A Middle Path: 30-Year with Extra Payments

You can take a 30-year mortgage and make extra principal payments to pay it off in 15–20 years. This gives you the flexibility of the lower required payment while aggressively building equity when you can afford to.

The downside: your rate will be higher than a true 15-year (typically 0.5–0.75% more), costing you extra in interest. But if income variability is a real concern, this hybrid approach is worth considering.

Run the Numbers for Your Loan

The right answer depends entirely on your loan amount, the actual rates you're offered, and your financial situation. Use the comparison calculator above for a quick side-by-side, or our Mortgage Calculator to see your full monthly payment including property taxes, insurance, and PMI.

Key Takeaways

• A 15-year mortgage saves ~$288,000 in interest on a $350,000 loan vs a 30-year
• The monthly payment is ~$700 higher — you need higher income and cash flow to manage it
• After 10 years, the 15-year borrower has paid down ~3.9x as much principal
• The 30-year gives flexibility; the 15-year forces faster wealth-building
• "Invest the difference" only works if you actually do it, consistently, for decades
• A 30-year with extra payments is a valid middle path if income variability is a concern
• If you're over 45, the age at payoff is often the deciding factor