On a $400,000 mortgage, choosing a 15-year over a 30-year can save $180,000 in interest — but the 30-year lets you keep $1,000/month for other priorities. Here is the real math, not the slogans.
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Mortgage term is the single largest financial decision most households ever make. A 15-year loan forces discipline and saves massive interest; a 30-year offers cash-flow freedom. The "right" answer depends on rate spread, other investment options, and how stable your income is. Let us run the numbers honestly.
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Lenders advertise 15-year rates as dramatically lower than 30-year, but the spread is usually just 0.5–0.75%. On $400,000, that 0.6% over 15 years saves roughly $22,000 in interest vs refinancing a 30-year into a 15-year halfway through. The bigger saver is not the rate — it is the fact that interest compounds over half as many years.
If you invest the monthly delta ($714/month in the example above) in a low-cost index fund earning 8% historically, you end up with roughly $1.06 million after 30 years. The 15-year interest savings is only $351,000. The 30-year + invested difference beats the 15-year by about $700k — but only if you actually invest the difference every single month for 30 years. Most people do not.
The 15-year wins behaviorally for most households. Money left in a checking account tends to get spent. Money sent to principal cannot be touched. For anyone who is not already maxing retirement accounts and consistently investing, the 15-year is a safer bet — even though it is mathematically inferior in theory.
Ask yourself honestly: if you took the 30-year, would you actually invest the $714/month every month, or would you upgrade to a nicer car, a bigger vacation, and bigger restaurants?
The smartest move for many buyers is the 30-year mortgage with a self-imposed aggressive payoff schedule. You get the lower required payment (flexibility in a rough month), but you voluntarily add principal each month. The "50% strategy" — add half the delta to principal, invest the other half — gives you a 20-year payoff plus meaningful investment growth, with escape hatches in both directions.
Lenders cap debt-to-income ratio at roughly 43–50%. A 15-year payment eats more of your DTI budget, which means you qualify for less house. If you are buying at the top of your budget, the 30-year may be the only option that works. This is a real constraint, not a preference.
In a low-rate environment (3–4%), the 30-year is almost always the mathematically superior choice — the invested difference dominates. In a high-rate environment (7%+), the 15-year becomes more attractive because the guaranteed interest savings rival expected market returns. At 2026's 6.5–7% range, it is genuinely close, and behavior becomes the tiebreaker.
Answer honestly — we will match your situation to 15-Year Mortgage or 30-Year Mortgage.
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Yes, and it is legal with zero prepayment penalty on virtually all residential mortgages. You keep the flexibility of the lower required payment while saving almost as much interest as a 15-year.
Typically 0.5–0.75%. Lenders charge less for shorter loans because their risk horizon is shorter. The actual spread varies by credit score, down payment, and market conditions.
No. Closing costs are roughly the same. The differences are rate, monthly payment, and total interest.
Yes, by refinancing. This makes sense if rates have dropped or your income has grown. Watch closing costs — you typically need 3+ years of savings to break even.
The 30-year produces more total deductible interest, but at modern standard deduction levels ($15,000+), many homeowners no longer itemize. Do not lean on the deduction as a reason to take a longer loan.
Usually the 30-year. You keep more cash for furnishings, emergencies, and unexpected ownership costs. You can accelerate later when income grows.
Rates are slightly higher than 30-year, slightly lower than 15-year. Few lenders offer it and few borrowers take it. A 30-year with voluntary extra principal usually beats a 20-year.
No — the opposite. The higher required payment is harder to maintain during job loss. A 30-year is safer in downturns because you can fall back to the lower required payment.